Patent Application
20230002398
This application is based on and claims priority to Korean Patent Application Nos. 10-2020-0056667, filed on May 12, 2020 and 10-2021-0060729, filed on May 11, 2021 in the Korean Intellectual Property Office, and all the benefits accruing therefrom under 35 U.S.C. § 119, the entire content of which is incorporated by reference herein.
One or more embodiments relate to a heterocyclic compound having a novel structure and an organic light-emitting device including the same.
Organic light-emitting devices (OLEDs) are self-emissive devices that produce full-color images, and also have wide viewing angles, high contrast ratios, short response times, and excellent characteristics in terms of luminance, driving voltage, and response speed, compared to devices in the art.
In an example, an organic light-emitting device includes an anode, a cathode, and an organic layer between the anode and the cathode, wherein the organic layer includes an emission layer. A hole transport region may be located between the anode and the emission layer, and an electron transport region may be located between the emission layer and the cathode. Holes provided from the anode may move toward the emission layer through the hole transport region, and electrons provided from the cathode may move toward the emission layer through the electron transport region. The holes and the electrons recombine in the emission layer to produce excitons. These excitons transition from an excited state to a ground state to thereby generate light.
Various types of organic light emitting devices are known. However, there still remains a need in OLEDs having one or more, preferably all, of low voltage, high efficiency, high color purity, and long lifetime characteristics
Provided are a heterocyclic compound having a novel structure and an organic light-emitting device including the same, wherein the organic light-emitting device has low voltage, high efficiency, high color purity, and long lifetime characteristics.
Additional aspects will be set forth in part in the description, which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments of the disclosure.
An aspect of the present disclosure provides a heterocyclic compound represented by Formula 1-1 or 1-2:
wherein, in Formulae 1-1 and 1-2,
X1 may be B or N,
ring CY1, ring CY2, and ring CY3 may each independently be a C5-C30 carbocyclic group or a C1-C30 heterocyclic group,
at least one of ring CY1, ring CY2, and ring CY3 may include a pyrimidine group,
Y1, Y2, and Y3 may each independently be O, S, Se, B(R4), N(R4), C(R4)(R5), Si(R4)(R5), Ge(R4)(R5), P(R4), P(═O)(R4), P(═S)(R4), or Al(R4),
R1, R2, R3, R4, and R5 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, —SF5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C1-C60 alkyl group, a substituted or unsubstituted C2-C60 alkenyl group, a substituted or unsubstituted C2-C60 alkynyl group, a substituted or unsubstituted C1-C60 alkoxy group, a substituted or unsubstituted C1-C60 alkylthio group, a substituted or unsubstituted C3-C10 cycloalkyl group, a substituted or unsubstituted C1-C10 heterocycloalkyl group, a substituted or unsubstituted C3-C10 cycloalkenyl group, a substituted or unsubstituted C2-C10 heterocycloalkenyl group, a substituted or unsubstituted C6-C60 aryl group, a substituted or unsubstituted C7-C60 arylalkyl group, a substituted or unsubstituted C6-C60 aryloxy group, a substituted or unsubstituted C6-C60 arylthio group, a substituted or unsubstituted C1-C60 heteroaryl group, a substituted or unsubstituted C1-C60 heteroaryloxy group, a substituted or unsubstituted C1-C60 heteroarylthio group, a substituted or unsubstituted C2-C60 heteroarylalkyl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q1)(Q2), —Si(Q3)(Q4)(Q5), —B(Q6)(Q7), or —P(═O)(Q8)(Q9),
two neighboring groups from among R1 to R5 may be optionally bonded to each other to form a C5-C30 carbocyclic group unsubstituted or substituted with R10 or a C1-C30 heterocyclic group unsubstituted or substituted with R10, and R10 is the same as described in connection with R1,
a1 to a3 may each independently be an integer from 1 to 10,
any one of the following condition (i) to (iii) is satisfied,
(i) when any one of ring CY1, ring CY2, and ring CY3 contains pyrimidine, at least one of Y1 to Y3 is N(R4),
(ii) when two of ring CY1, ring CY2, and ring CY3 each contain pyrimidine, at least one of Y1 to Y3 is N(R4),
(iii) when each of ring CY1, ring CY2, and ring CY3 contains pyrimidine, Y1 to Y3 may each independently be Se, B(R4), N(R4), C(R4)(R5), Si(R4)(R5), Ge(R4)(R5), P(R4), P(═O)(R4), P(═S)(R4), or Al(R4),
at least one substituent of the substituted C5-C30 carbocyclic group, the substituted C1-C30 heterocyclic group, the substituted C1-C60 alkyl group, the substituted C2-C60 alkenyl group, the substituted C2-C60 alkynyl group, the substituted C1-C60 alkoxy group, the substituted C1-C60 alkylthio group, the substituted C3-C10 cycloalkyl group, the substituted C1-C10 heterocycloalkyl group, the substituted C3-C10 cycloalkenyl group, the substituted C2-C10 heterocycloalkenyl group, the substituted C6-C60 aryl group, the substituted C7-C60 arylalkyl group, the substituted C6-C60 aryloxy group, the substituted C6-C60 arylthio group, the substituted C1-C60 heteroaryl group, the substituted C1-C60 heteroaryloxy group, the substituted C1-C60 heteroarylthio group, the substituted C2-C60 heteroarylalkyl group, the substituted monovalent non-aromatic condensed polycyclic group, or the substituted monovalent non-aromatic condensed heteropolycyclic group may be
deuterium, —F, —Cl, —Br, —I, —CD3, —CD2H, —CDH2, —CF3, —CF2H, —CFH2, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkylthio group, or a C1-C60 alkoxy group,
a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkylthio group, or a C1-C60 alkoxy group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, —CD3, —CD2H, —CDH2, —CF3, —CF2H, —CFH2, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C2-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C7-C60 arylalkyl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a C1-C60 heteroaryloxy group, a C1-C60 heteroarylthio group, a C2-C60 heteroarylalkyl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —Si(Q11)(Q12)(Q13), —N(Q14)(Q15), —B(Q16)(Q17), or —P(═O)(Q18)(Q19),
a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C2-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C7-C60 arylalkyl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a C1-C60 heteroaryloxy group, a C1-C60 heteroarylthio group, a C2-C60 heteroarylalkyl group, a monovalent non-aromatic condensed polycyclic group, or a monovalent non-aromatic condensed heteropolycyclic group,
a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C2-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C7-C60 arylalkyl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a C1-C60 heteroaryloxy group, a C1-C60 heteroarylthio group, a C2-C60 heteroarylalkyl group, a monovalent non-aromatic condensed polycyclic group, or a monovalent non-aromatic condensed heteropolycyclic group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, —CD3, —CD2H, —CDH2, —CF3, —CF2H, —CFH2, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkoxy group, a C1-C60 alkylthio group, a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C2-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C7-C60 arylalkyl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a C1-C60 heteroaryloxy group, a C1-C60 heteroarylthio group, a C2-C60 heteroarylalkyl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —Si(Q21)(Q22)(Q23), —N(Q24)(Q25)-B(Q26)(Q27), or —P(═O)(Q28)(Q29), or
—Si(Q31)(Q32)(Q33), —N(Q34)(Q35), —B(Q36)(Q37), or —P(═O)(Q38)(Q39),
wherein Q1 to Q9, Q11 to Q19, Q21 to Q29, and Q31 to Q39 are each independently hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C1-C60 alkyl group, a substituted or unsubstituted C2-C60 alkenyl group, a substituted or unsubstituted C2-C60 alkynyl group, a substituted or unsubstituted C1-C60 alkoxy group, a substituted or unsubstituted C1-C60 alkylthio group, a substituted or unsubstituted C3-C10 cycloalkyl group, a substituted or unsubstituted C1-C10 heterocycloalkyl group, a substituted or unsubstituted C3-C10 cycloalkenyl group, a substituted or unsubstituted C2-C10 heterocycloalkenyl group, a substituted or unsubstituted C6-C60 aryl group, a substituted or unsubstituted C7-C60 arylalkyl group, a substituted or unsubstituted C6-C60 aryloxy group, a substituted or unsubstituted C6-C60 arylthio group, a substituted or unsubstituted C1-C60 heteroaryl group, a substituted or unsubstituted C1-C60 heteroaryloxy group, a substituted or unsubstituted C1-C60 heteroarylthio group, a substituted or unsubstituted C2-C60 heteroarylalkyl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, or a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group.
Another aspect provides an organic light-emitting device including a first electrode, a second electrode, and an organic layer including an emission layer between the first electrode and the second electrode, wherein the organic layer includes the heterocyclic compound represented by Formula 1-1 or 1-2.
The above and other aspects, features, and advantages of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:
Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout the specification. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the figures, to explain aspects. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list, for example, “at least one of a, b, or c” indicates only a, only b, only c, both a and b, both a and c, both b and c, all of a, b, and c, or variations thereof.
It will be understood that when an element is referred to as being “on” another element, it can be directly in contact with the other element or intervening elements may be present therebetween. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present.
It will be understood that, although the terms first, second, third etc. may be used herein to describe various elements, components, regions, layers, and/or sections, these elements, components, regions, layers, and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Thus, a first element, component, region, layer, or section discussed below could be termed a second element, component, region, layer, or section without departing from the teachings of the present embodiments.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.
The term “or” means “and/or.” It will be further understood that the terms “comprises” and/or “comprising,” or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this general inventive concept belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
Exemplary embodiments are described herein with reference to cross section illustrations that are schematic illustrations of idealized embodiments. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments described herein should not be construed as limited to the particular shapes of regions as illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, a region illustrated or described as flat may, typically, have rough and/or nonlinear features. Moreover, sharp angles that are illustrated may be rounded. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region and are not intended to limit the scope of the present claims.
“About” or “approximately” as used herein is inclusive of the stated value and means within an acceptable range of deviation for the particular value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the particular quantity (i.e., the limitations of the measurement system). For example, “about” can mean within one or more standard deviations, or within ±20%, 10%, 5% of the stated value.
In any formula, * and *′ each indicate a binding site to a neighboring atom or a neighboring functional group.
An aspect of the present disclosure provides a heterocyclic compound represented by Formula 1-1 or 1-2 below:
Formulae 1-1 and 1-2 will be described in detail.
X1 in Formulae 1-1 and 1-2 may be B or N. For example, X1 may be B.
Ring CY1, ring CY2, and ring CY3 in Formulae 1-1 and 1-2 may each independently be a C5-C30 carbocyclic group or a C1-C30 heterocyclic group, and at least one of ring CY1, ring CY2, and ring CY3 may include a pyrimidine group.
In an embodiment, ring CY1, ring CY2, and ring CY3 may each independently be group A, group B, a condensed ring in which two or more groups of group A are condensed with each other, a condensed ring in which two or more groups of group B are condensed with each other, or a condensed ring in which at least one group A is condensed with at least one group B.
Group A may be a cyclopenta-1,3-diene group, an indene group, an azulene group, a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a tetracene group, a tetraphene group, a pyrene group, a chrysene group, a triphenylene group, or a fluorene group, or
Group B may be a furan group, a thiophene group, a pyrrole group, borole group, a silole group, a pyrrolidine group, an imidazole group, a triazole group, an oxazole group, an isoxazole group, a thiazole group, an isothiazole group, a pyridine group, a pyrimidine group, a pyridazine group, a triazine group, an indole group, an isoindole group, an indolizine group, a quinoline group, an isoquinoline group, a quinoxaline group, an isoquinoxaline group, a carbazole group, a dibenzofuran group, a dibenzothiophene group, a dibenzosilole group, or a dibenzoborole group.
For example, ring CY1, ring CY2, and ring CY3 may each independently be a benzene group, a naphthalene group, a fluorene group, a pyridine group, a pyrimidine group, a pyrazine group, a quinoline group, an isoquinoline group, a quinazoline group, a quinoxaline group, a phthalazine group, a carbazole group, an azacarbazole group, a dibenzofuran group, a dibenzothiophene group, a dibenzoselenophene group, a dibenzosilole group, an azadibenzofuran group, an azadibenzothiophene group, an azadibenzoselenophene group, or an azadibenzosilole group, but embodiments of the present disclosure are not limited thereto.
In an embodiment, when 1 or 2 rings of the ring CY1 to ring CY3 include a pyrimidine group, the remaining ring may be a benzene group, a naphthalene group, or a fluorene group.
For example, ring CY3 may be a pyrimidine group and ring CY1 and ring CY2 may each be a benzene group; ring CY1 and ring CY2 may each be a pyrimidine group and ring CY3 may be a benzene group; or ring CY1, ring CY2, and ring CY3 may each be a pyrimidine group, but embodiments of the present disclosure are not limited thereto.
Y1, Y2, and Y3 in Formulae 1-1 and 1-2 may each independently be O, S, Se, B(R4), N(R4), C(R4)(R5), Si(R4)(R5), Ge(R4)(R5), P(R4), P(═O)(R4), P(═S)(R4), or Al(R4).
In an embodiment, at least one of Y1 to Y3 may be N(R4). For example, each of Y1 to Y3 may be N(R4), but embodiments of the present disclosure are not limited thereto.
In an embodiment, X1 may be B and each of Y1 and Y2 may be N(R4).
In an embodiment, X1 may be B and Y1 to Y3 may be identical to each other. For example, X1 may be B and Y1 to Y3 may each be C(R4)(R5) or N(R4).
R1, R2, R3, R4 and R5 in Formulae 1-1 and 1-2 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, —SF5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C1-C60 alkyl group, a substituted or unsubstituted C2-C60 alkenyl group, a substituted or unsubstituted C2-C60 alkynyl group, a substituted or unsubstituted C1-C60 alkoxy group, a substituted or unsubstituted C1-C60 alkylthio group, a substituted or unsubstituted C3-C10 cycloalkyl group, a substituted or unsubstituted C1-C10 heterocycloalkyl group, a substituted or unsubstituted C3-C10 cycloalkenyl group, a substituted or unsubstituted C2-C10 heterocycloalkenyl group, a substituted or unsubstituted C6-C60 aryl group, a substituted or unsubstituted C7-C60 arylalkyl group, a substituted or unsubstituted C6-C60 aryloxy group, a substituted or unsubstituted C6-C60 arylthio group, a substituted or unsubstituted C1-C60 heteroaryl group, a substituted or unsubstituted C1-C60 heteroaryloxy group, a substituted or unsubstituted C1-C60 heteroarylthio group, a substituted or unsubstituted C2-C60 heteroarylalkyl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q1)(Q2), —Si(Q3)(Q4)(Q5), —B(Q6)(Q7), or —P(═O)(Q8)(Q), and neighboring two groups of R1 to R5 may optionally be bonded to form a C5-C30 carbocyclic group unsubstituted or substituted with R10 or a C1-C30 heterocyclic group unsubstituted or substituted with R10. In this regard, R10 may be the same as described in connection with R1.
In an embodiment, R1 to R5 may each independently be:
hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group (CN), a nitro group, an amino group, a C1-C60 alkyl group, a C1-C60 alkylthio group, or a C1-C60 alkoxy group;
a C1-C60 alkyl group, a C1-C60 alkylthio group, or a C1-C60 alkoxy group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group (CN), a nitro group, an amino group, a phenyl group, a biphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, or a chrysenyl group;
a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, or a carbazolyl group;
a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, or a carbazolyl group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group (CN), a nitro group, an amino group, a C1-C60 alkyl group, a C1-C60 alkoxy group, a C1-C60 alkylthio group, a C7-C60 arylalkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a carbazolyl group, —Si(Q31)(Q32)(Q33), —N(Q34)(Q35), —B(Q36)(Q37), or —P(═O)(Q38)(Q39); or
—N(Q1)(Q2), —Si(Q3)(Q4)(Q5), —B(Q6)(Q7), or —P(═O)(Q8)(Q9),
but embodiments of the present disclosure are not limited thereto.
For example, R1 to R3 may each independently be:
hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, a tert-pentyl group, a neo-pentyl group, an iso-pentyl group, a sec-pentyl group, a 3-pentyl group, a sec-isopentyl group, an n-hexyl group, an iso-hexyl group, a sec-hexyl group, or a tert-hexyl group; or
a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, a tert-pentyl group, a neo-pentyl group, an iso-pentyl group, a sec-pentyl group, a 3-pentyl group, a sec-isopentyl group, an n-hexyl group, an iso-hexyl group, a sec-hexyl group, or a tert-hexyl group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, or a phenyl group.
For example, R4 and R5 may each independently be:
hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group (CN), a nitro group, an amino group, a C1-C60 alkyl group, a C1-C60 alkylthio group, or a C1-C60 alkoxy group;
a C1-C60 alkyl group, a C1-C60 alkylthio group, or a C1-C60 alkoxy group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group (CN), a nitro group, an amino group, or a phenyl group; and
a group represented by one of Formulae 4-1 to 4-42, but embodiments of the present disclosure are not limited thereto:
wherein, in Formulae 4-1 to 4-42,
Y31 may be O, S, C(Z43)(Z44), N(Z43), or Si(Z43)(Z44),
Z41 to Z44 may each independently be:
hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C1-C20 alkyl group, a C1-C20 alkoxy group, a C1-C20 alkylthio group, a C7-C60 arylalkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, or a carbazolyl group;
a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, or a carbazolyl group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C1-C20 alkyl group, a C1-C20 alkoxy group, a C1-C20 alkylthio group, or a C7-C60 arylalkyl group (for example, a cumyl group),
f3 may be an integer from 1 to 3,
f4 may be an integer from 1 to 4,
f5 may be an integer from 1 to 5,
f6 may be an integer from 1 to 6,
f7 may be an integer from 1 to 7,
f9 may be an integer from 1 to 9,
* indicates a binding site to a neighboring atom, and
substituent Z41 is present on each ring through which the bond with the substituent Z41 passes.
For example, R4 and R5 may each independently be:
hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, a tert-pentyl group, a neo-pentyl group, an iso-pentyl group, a sec-pentyl group, a 3-pentyl group, a sec-isopentyl group, an n-hexyl group, an iso-hexyl group, a sec-hexyl group, or a tert-hexyl group; or
a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, a tert-pentyl group, a neo-pentyl group, an iso-pentyl group, a sec-pentyl group, a 3-pentyl group, a sec-isopentyl group, an n-hexyl group, an iso-hexyl group, a sec-hexyl group, or a tert-hexyl group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, or a phenyl group; and
a group represented by one of Formulae 4-1 to 4-8, and
Y31 in Formulae 4-5 to 4-8 may be S, C(Z43)(Z44), N(Z43), or Si(Z43)(Z44).
In Formulae 1-1 and 1-2, a1 indicates the number of R1(s) and may be an integer from 1 to 10, wherein, when a1 is 2 or more, two or more of R1(s) may be identical to or different from each other; a2 indicates the number of R2(s) and may be an integer from 1 to 10, wherein, when a2 is 2 or more, two or more of R2(s) may be identical to or different from each other; and a3 indicates the number of R3(s) and may be an integer from 1 to 10, wherein, when a3 is 2 or more, two or more of R3(s) may be identical to or different from each other.
A heterocyclic compound represented by Formula 1-1 or 1-2 may satisfy any of the following conditions (i) to (iii):
(i) when any one of ring CY1, ring CY2, and ring CY3 contains pyrimidine, at least one of Y1 to Y3 is N(R4);
(ii) when two of ring CY1, ring CY2, and ring CY3 each contain pyrimidine, at least one of Y1 to Y3 is N(R4); and
(iii) when each of ring CY1, ring CY2, and ring CY3 contains pyrimidine, Y1 to Y3 may each independently be Se, B(R4), N(R4), C(R4)(R5), Si(R4)(R5), Ge(R4)(R5), P(R4), P(═O)(R4), P(═S)(R4), or Al(R4).
In an embodiment, the heterocyclic compound may be represented by one of Formulae 2-1 to 2-25:
wherein, in Formulae 2-1 to 2-25,
ring CY1, ring CY2, ring CY3, X1, Y1, Y2, Y3, R1, R2, R3, a1, a2, and a3 are the same as described in the present specification,
R1a to R1d are each independently the same as described in connection with R1,
R2a to R2d are each independently the same as described in connection with R2,
R3a is the same as described in connection with R3, and
R10a to R10h are each independently the same as described in connection with R10.
For example, in Formulae 2-1 to 2-13 and 2-18 to 2-23,
ring CY1 to ring CY3 may each independently be a benzene group, a naphthalene group, or a fluorene group.
In an embodiment, the heterocyclic compound may be of Compounds of groups 2-1 to 2-25 below:
The compounds are represented by the formula 2-1 below, wherein CY2 and CY3 are each a benzene group, X1 is B, and Y1, Y2, R1b, R1d, (R2)a2, (R3)a3 are each shown in the table 1 below,
The compounds are represented by the formula 2-2 below, wherein CY2 and CY3 are each a benzene group, X1 is B, and Y1, Y2, R1a, R1c, (R2)a2, (R3)a3 are each shown in the table 2 below,
The compounds are represented by the formula 2-3 below, wherein CY1 and CY3 are each a benzene group, X1 is B, and Y1, Y2, R2b, R2d, (R1)a1, (R3)a3 are each shown in the table 3 below,
The compounds are represented by the formula 2-4 below, wherein CY1 and CY3 are each a benzene group, X1 is B, and Y1, Y2, R2a, R2c, (R1)a1, (R3)a3 are each shown in the table 4 below,
The compounds are represented by the formula 2-5 below, wherein CY1 and CY2 are each a benzene group, X1 is B, and Y1, Y2, R3a, (R1)a1, (R2)a2 are each shown in the table 5 below,
The compounds are represented by the formula 2-6 below, wherein CY3 is a benzene group, X1 is B, and Y1, Y2, R1b, R1d, R2b, R2d, (R3)a3 are each shown in the table 6 below,
The compounds are represented by the formula 2-7 below, wherein CY3 is a benzene group, X1 is B, and Y1, Y2, R1b, R1d, R2a, R2c, (R3)a3 are each shown in the table 7 below,
The compounds are represented by the formula 2-8 below, wherein CY3 is a benzene group, X1 is B, and Y1, Y2, R1a, R1c, R2b, R2d, (R3)a3 are each shown in the table 8 below,
The compounds are represented by the formula 2-9 below, wherein CY3 is a benzene group, X1 is B, and Y1, Y2, R1a, R1c, R2a, R2c, (R3)a3 are each shown in the table 9 below,
The compounds are represented by the formula 2-10 below, wherein CY2 is a benzene group, X1 is B, and Y1, Y2, R1b, R1d, R3a, (R2)a2 are each shown in the table 10 below,
The compounds are represented by the formula 2-11 below, wherein CY2 is a benzene group, X1 is B, and Y1, Y2, R1a, R1c, R3a, (R2)a2 are each shown in the table 11 below,
The compounds are represented by the formula 2-12 below, wherein CY1 is a benzene group, X1 is B, and Y1, Y2, R2b, R2d, R3a, (R1)a1 are each shown in the table 12 below.
The compounds are represented by the formula 2-13 below, wherein CY1 is a benzene group, X1 is B, and Y1, Y2, R2a, R2c, R3a, (R1)a1 are each shown in the table 13 below,
The compounds are represented by the formula 2-14 below, wherein X1 is B, and Y1, Y2, R1b, R1d, R2b, R2d, R3a are each shown in the table 14 below,
The compounds are represented by the formula 2-15 below, wherein X1 is B, and Y1, Y2, R1b, R1d, R2a, R2c, R3a are each shown in the table 15 below,
The compounds are represented by the formula 2-16 below, wherein X1 is B, and Y1, Y2, R1a, R1c, R2b, R2d, R3a are each shown in the table 16 below,
The compounds are represented by the formula 2-17 below, wherein X1 is B, and Y1, Y2, R1a, R1c, R2a, R2c, R3a are each shown in the table 17 below,
The compounds are represented by the formula 2-18 below, wherein CY2 and CY3 are each a benzene group, X1 is B, and Y1, Y2, Y3, R1b, (R2)a2, (R3)a3 are each shown in the table 18 below,
The compounds are represented by the formula 2-19 below, wherein CY1 and CY3 are each a benzene group, X1 is B, and Y1, Y2, Y3, R2b, (R1)a1, (R3)a3 are each shown in the table 19 below,
The compounds are represented by the formula 2-20 below, wherein CY1 and CY2 are each a benzene group, X1 is B, and Y1, Y2, Y3, R3a, (R1)a1, (R2)a2 are each shown in the table 20 below,
The compounds are represented by the formula 2-21 below, wherein CY3 is a benzene group, X1 is B, and Y1, Y2, Y3, R1b, R2b, (R3)a3 are each shown in the table 21 below,
The compounds are represented by the formula 2-22 below, wherein CY2 is a benzene group, X1 is B, and Y1, Y2, Y3, R1b, R3a, (R2)a2 are each shown in the table 22 below,
The compounds are represented by the formula 2-23 below, wherein CY1 is a benzene group X1 is B, and Y1, Y2, Y3, R2b, R3a, (R1)a1 are each shown in the table 23 below,
The compounds are represented by the formula 2-24 below, wherein X1 is B, and Y1, Y2, Y3, R1b, R2b, R3a are each shown in the table 24 below,
The compounds are represented by the formula 2-25 below, wherein X1 is B, and R1 b, R1c, R1d, R2b, R2c, R2d, R3a, R10a, R10b, R10c, R10d, R10e, R10f, R10g, R10h are each shown in the table 25 below,
wherein in the tables 1 to 25 regarding the groups 2-1 to 2-25 above, “t-bu” indicates “tert-butyl group” and “N-Ph”, “N-tolyl”, “N-Biph”, “a1”, “a2”, “a3”, “a4”, “a5”, “a6”, “b1”, “b2”, “b3”, “b4”, “b5”, “b6”, “b7”, “b8”, “b9”, and “b10” indicates as shown below, and Y indicates Y1, Y2 or Y3:
In an embodiment, the heterocyclic compound represented by Formula 1-1 or 1-2, at least one of ring CY1 to ring CY3 includes a pyrimidine group. While not wishing to be bound by theory, it is understood that when at least one of ring CY1 to ring CY3 includes a pyrimidine group, the multi-resonance effect is improved and the ΔEst value is remarkably reduced, resulting in high efficiency and the color purity effect.
Synthesis method of the heterocyclic compound represented by Formula 1-1 or 1-2 may be recognized by those skilled in the art with reference to the Synthesis Examples provided herein.
In an embodiment, the heterocyclic compound represented by Formula 1-1 or 1-2 is used in an organic layer of an organic light-emitting device, for example, used as a dopant of an emission layer of the organic layer. Another aspect of the present disclosure provides an organic light-emitting device including a first electrode, a second electrode, and an organic layer which is located between the first electrode and the second electrode, includes an emission layer, and at least one of heterocyclic compounds represented by Formula 1-1 or 1-2.
The organic light-emitting device may include an organic layer including the heterocyclic compound represented by Formula 1-1 or 1-2 as described above. In an embodiment, such an organic light-emitting device may have low driving voltage, high or improved efficiency, high or improved power, high or improved quantum efficiency, long or improved lifespan, a low roll-off ratio, and excellent or improved color purity.
The heterocyclic compound represented by Formula 1-1 or 1-2 may be used between a pair of electrodes in an organic light-emitting device. For example, the heterocyclic compound represented by Formula 1-1 or 1-2 may be included in the emission layer. In an embodiment, the heterocyclic compound may act as a dopant, and the emission layer may further include a host (that is, the amount of heterocyclic compound represented by Formula 1-1 or 1-2 may be less than the amount of the host).
The expression “an organic layer includes at least one heterocyclic compound” as used herein may include a case in which “an organic layer includes identical heterocyclic compounds represented by Formula 1-1 or 1-2” and a case in which “an organic layer includes two or more different heterocyclic compounds represented by Formula 1-1 or 1-2”.
For example, the organic layer may include, as the heterocyclic compound, only Compound 1. In an embodiment, Compound 1 may be included in the emission layer of the organic light-emitting device. In an embodiment, the organic layer may include, as the heterocyclic compound, Compound 1 and Compound 2. In an embodiment, Compound 1 and Compound 2 may exist in an identical layer (for example, Compound 1 and Compound 2 all may exist in an emission layer).
The first electrode may be an anode, which is a hole injection electrode, and the second electrode may be a cathode, which is an electron injection electrode; or the first electrode may be a cathode, which is an electron injection electrode, and the second electrode may be an anode, which is a hole injection electrode.
In an embodiment, in the organic light-emitting device, the first electrode is an anode, and the second electrode is a cathode, and the organic layer further includes a hole transport region between the first electrode and the emission layer and an electron transport region between the emission layer and the second electrode, and the hole transport region includes a hole injection layer, a hole transport layer, an electron blocking layer, or any combination thereof, and the electron transport region includes a hole blocking layer, an electron transport layer, an electron injection layer, a buffer layer, or any combination thereof.
The term “organic layer” used herein refers to a single layer and/or a plurality of layers between the first electrode and the second electrode of the organic light-emitting device. The “organic layer” may include, in addition to an organic compound, an organometallic complex including metal.
In an embodiment, the heterocyclic compound may be a fluorescent emitter capable of emitting fluorescent light. An emission layer emitting the fluorescent light is clearly distinguished from an emission layer of the related art that emits phosphorescent light.
In an embodiment, the emission layer may further include a sensitizer that satisfies Equation 1 below, and the amount of the host may be greater than the sum of the amount of the sensitizer and the heterocyclic compound:
ΔEST≤0.3 eV Equation 1
In an embodiment, ΔEST refers to the energy difference between the lowest excited singlet (S1) and the lowest excited triplet (T1).
The triplet energy level and the singlet energy level are evaluated using the density functional theory (DFT) method of the Gaussian program, which is structure-optimized at the B3LYP/6-31G(d,p) level.
The sensitizer and the heterocyclic compound may satisfy Conditions 1 and 2:
T
decay(HC)<Tdecay(S) Condition 1
T
decay(HC)<1.5 μs Condition 2
wherein, in Conditions 1 and 2,
Tdecay (HC) is the decay time of the heterocyclic compound, and
Tdecay(S) is the decay time of the sensitizer.
The decay time of the heterocyclic compound is calculated from a time-resolved photoluminescence (TRPL) at room temperature with respect to a 40 nanometer (nm)-thickness film (hereinafter referred to as “Film (CD)”) obtained by vacuum-codepositing the host and the heterocyclic compound included in the emission layer at the weight ratio of about 90:10 on a quartz substrate at the vacuum degree of 10−7 torr.
The decay time of the sensitizer is calculated from TRPL at room temperature with respect to a 40 nm-thickness film (hereinafter referred to as “Film (S)”) obtained by vacuum-codepositing the host and the sensitizer at the weight ratio of about 90:10 on a quartz substrate at the vacuum degree of 10−7 torr.
In general, it is known that since triplet excitons stay long in an excited state, they influence the decrease in the lifespan of organic light-emitting devices. While not wishing to be bound by theory, it is understood that, due to the use of the heterocyclic compound, the time during which the sensitizer stays in the triplet excitons is reduced, and thus, the lifespan of an organic light-emitting device including the same may be prolonged.
In an embodiment, the more triplet excitons the sensitizer has, the more excess energy is accumulated in the sensitizer, resulting in more hot excitons. That is, the amount of triplet excitons of the sensitizer is proportional to the amount of hot excitons. The hot excitons break down various chemical bonds of a compound included in an emission layer and/or a compound existing at the interface of the emission layer and other layers to decompose the compound, and the lifespan of organic light-emitting devices may be reduced. While not wishing to be bound by theory, it is understood that, by using heterocyclic compounds, the triplet excitons of the sensitizer can be quickly converted to singlet excitons of the heterocyclic compounds, ultimately reducing the amount of hot excitons and increasing or improving the lifespan of an organic light-emitting device.
In an embodiment, “hot excitons” may be generated or increased by exciton-exciton annihilation due to an increase in the density of excitons in an emission layer, exciton-charge annihilation due to the charge imbalance in an emission layer, and/or radical ion pairs due to the delivery of electrons between a host and a heterocyclic compound.
In order to quickly convert triplet excitons of the sensitizer to singlet excitons of the heterocyclic compound, Condition 1 should be satisfied.
While not wishing to be bound by theory, it is understood that, since the heterocyclic compound emits fluorescent light, a high or improved color purity organic light-emitting device can be provided, and in particular, since Condition 2 is satisfied, the singlet excitons of the heterocyclic compound excited state at room temperature can be rapidly transferred, and thus, the single state of the heterocyclic compound in the excited state may not be accumulated, and the lifespan of an organic light-emitting device may be increased or improved.
In an embodiment, when Condition 3 is further satisfied, the transition from the triplet excitons of the sensitizer to the singlet excitons of the heterocyclic compound may occur more smoothly, and the lifespan of an organic light-emitting device may be further prolonged or improved:
T
decay(HC)/Tdecay(S)<0.5 Condition 3
wherein, in Condition 3,
Tdecay (HC) is the decay time of the heterocyclic compound, and
Tdecay(S) is a decay time of the sensitizer.
In an embodiment, the organic light-emitting device may further satisfy Condition 4:
BDE(S)−T1(S)<3.0 electronvolt (eV) Condition 4
wherein, in Condition 4,
BDE (S) is the bond dissociation energy level of the sensitizer, and
T1 (S) is the lowest excitation triplet energy level of the sensitizer.
In an embodiment, the organic light-emitting device may have the target level of lifespan by satisfying Condition 5 below:
R(Hex)/e10<15 Condition 5
wherein, in Condition 5,
R (Hex) is the production rate of hot excitons.
In an embodiment, R (Hex) was subjected to the photochemical stability of the organic light-emitting device (photochemical stability), and then calculated through the Gaussian 09 program according to Equation C below,
R(Hex)=a×Tdecay(S)×e−(BDE(S)−T
wherein, in Equation C,
a is a constant,
Tdecay(S) is a decay time of the sensitizer,
BDE (S) is the bond dissociation energy level of the sensitizer, and
T1 (S) is the lowest excitation triplet energy level of the sensitizer.
The hot-exciton production rate is estimated to be proportional to (decay time)×e-(BDE-T1), and in order to obtain the target level of the lifespan of the organic light-emitting device, (hot-exciton production rate)/e10 should be less than about 15, for example, less than about 12, less than about 10, less than about 8, less than about 6, less than about 4, less than about 2, or less than about 1.
The degradation analysis (PCS) of organic light-emitting devices was calculated according to the following Equation P:
PCS(%)=I2/I1×100 Equation P
wherein, in Equation P,
I1, with respect to a film formed by depositing a compound of which PCS is to be measured, is a maximum light intensity obtained from the PL spectrum which is evaluated at room temperature under Argon (Ar) atmosphere where ambient air is blocked immediately after the formation of the film by using a He—Cd laser (excitation wavelength=325 nanometers, laser power density)=100 mW/cm2) of KIMMON-KOHA Inc., and
I2, with respect to a film formed by depositing a compound of which PCS is to be measured, is a maximum light intensity obtained from the PL spectrum which is evaluated at room temperature under Ar atmosphere where ambient air is blocked, by exposing the film to light of the He—Cd laser (excitation wavelength=325 nanometers and laser power density=100 milliwatts per square centimeter (mW/cm2)) of KIMMON-KOHA Inc., which is a pumping laser which has been used to evaluate 11, for 3 hours, and then, using He—Cd laser of KIMMON-KOHA Inc. (excitation wavelength=325 nanometers). In the case of the sensitizer, reverse intersystem crossing (RISC) and/or intersystem crossing (ISC) actively occur, which allows excitons generated at the host to be delivered to the heterocyclic compound.
The general energy transfer of an organic light-emitting device (type I) according to an embodiment will be described with reference to
Singlet and triplet excitons are formed at the host in the emission layer, and the singlet and triplet excitons formed at the host are transferred to the sensitizer and then to the heterocyclic compound through Förster energy transfer (FRET). At this time, in order to embody the high or improved efficiency and long or improved lifespan of the organic light-emitting device, it is desirable to control the hot excitons generated in the emission layer, which may require optimization of energy transfer.
The general energy transfer of an organic light-emitting device (type I) according to an embodiment will be described with reference to
The singlet excitons formed at the host, which is about 25% of the total excitons, are transferred to the sensitizer through FRET, and the energy of triplet excitons formed at the host, which is about 75% of the total excitons, is transferred to the singlet and triplet of the sensitizer, among which the energy delivered to triplet is subjected to RISC into singlet, and then, the singlet energy of the sensitizer is transferred to the heterocyclic compound through FRET.
The general energy transfer of an organic light-emitting device (type II) according to an embodiment will be described with reference to
The triplet excitons formed at the host, which is about 75% of the total excitons, are transferred to the sensitizer through Dexter energy transfer, and the energy of singlet excitons formed at the host, which is about 25% of the total excitons, is transferred to the singlet and triplet of the sensitizer, among which the energy delivered to singlet is subjected to ISC into triplet, and then, the triplet energy of the sensitizer is transferred to the heterocyclic compound through FRET.
While not wishing to be bound by theory, it is understood that by transferring all the singlet excitons and triplet excitons generated in the emission layer to the heterocyclic compound, an organic light-emitting device having improved efficiency can be obtained. In an embodiment, since an organic light-emitting device can be obtained with significantly reduced energy loss, the lifespan characteristics of the organic light-emitting device can be improved.
The amount of the sensitizer in the emission layer may be from about 5 weight percent (wt %) to about 50 wt % with respect to the total weight of the emission layer, for example, from about 5 wt % to about 40 wt %, from about 5 wt % to about 30 wt %, from about 5 wt % to about 20 wt %, from about 5 wt % to about 10 wt %, from about 10 wt % to about 50 wt %, from about 15 wt % to about 50 wt %, from about 20 wt % to about 50 wt %, from about 25 wt % to about 50 wt %, from about 30 wt % to about 50 wt %, from about 35 wt % to about 50 wt %, from about 40 wt % to about 50 wt %, or from about 45 wt % to about 50 wt % with respect to the total weight of the emission layer. While not wishing to be bound by theory, it is understood that within these ranges, it is possible to achieve effective energy transfer in the emission layer, and accordingly, an organic light-emitting device having high or improved efficiency and long or improved lifespan can be obtained.
In an embodiment, the host, the heterocyclic compound, and the sensitizer may satisfy Condition 6:
T
1(H)≥T1(S)≥S1(HC) Condition 6
wherein, in Condition 6,
T1(H) is the lowest excited triplet energy level of the host,
S1(HC) is the lowest excitation singlet energy level of the heterocyclic compound, and
T1(S) is the lowest excitation triplet energy level of the sensitizer.
While not wishing to be bound by theory, it is understood that when the host, the heterocyclic compound, and the sensitizer further satisfy condition 6, triplet excitons may be effectively transferred from the host to the heterocyclic compound, thereby obtaining an organic light-emitting device with improved efficiency.
The emission layer may include the host, the heterocyclic compound, and the sensitizer. That is, the emission layer may not further include materials other than the host, the heterocyclic compound, and the sensitizer.
In an embodiment, the emission layer may further include a light-emitting dopant, and in this case, the amount of the host may be greater than the total amount of the light emitting dopant and the heterocyclic compound represented by Formula 1-1 or 1-2. The light-emitting dopant may include a light-emitting dopant having S1 and T1 energy levels suitable for receiving energy from the excitation S1 energy level of the heterocyclic compound. In an embodiment, the heterocyclic compound may act as a sensitizer that transfers energy. In an embodiment, the heterocyclic compound and the light-emitting dopant may satisfy the same relationship of the sensitizer and the heterocyclic compound described above.
The emission layer may emit deep blue light. For example, the blue light refers to light having the wavelength range of about 380 nm to about 490 nm.
A substrate may be additionally located under the first electrode 11 or above the second electrode 19. For use as the substrate, any suitable substrate that is used in organic light-emitting devices available in the art may be used, and the substrate may be a glass substrate or a transparent plastic substrate, each having excellent or suitable mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water resistance.
In an embodiment, the first electrode 11 may be formed by depositing or sputtering a material for forming the first electrode 11 on the substrate. The first electrode 11 may be an anode. The material for forming the first electrode 11 may be materials with a high work function to facilitate hole injection. The first electrode 11 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. The material for forming the first electrode 11 may be indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO2), or zinc oxide (ZnO). In an embodiment, the material for forming the first electrode 11 may be metal, such as magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), or magnesium-silver (Mg—Ag).
The first electrode 11 may have a single-layered structure or a multi-layered structure including two or more layers. For example, the first electrode 11 may have a three-layered structure of ITO/Ag/ITO, but the structure of the first electrode 11 is not limited thereto.
The organic layer 15 is located on the first electrode 11.
The organic layer 15 may include a hole transport region, an emission layer, and an electron transport region.
The hole transport region may be between the first electrode 11 and the emission layer.
The hole transport region may include at least one of a hole injection layer, a hole transport layer, an electron blocking layer, or a buffer layer.
The hole transport region may include only either a hole injection layer or a hole transport layer. In an embodiment, the hole transport region may have a hole injection layer/hole transport layer structure or a hole injection layer/hole transport layer/electron blocking layer structure, wherein, for each structure, each layer is sequentially stacked in this stated order from the first electrode 11.
When the hole transport region may include a hole injection layer (HIL), the hole injection layer may be formed on the first electrode 11 by using one or more suitable methods, for example, vacuum deposition, spin coating, casting, and/or Langmuir-Blodgett (LB) deposition.
In an embodiment, when a hole injection layer is formed by vacuum deposition, the deposition conditions may vary according to a material that is used to form the hole injection layer, and the structure and thermal characteristics of the hole injection layer. For example, the deposition conditions may include a deposition temperature of about 100° C. to about 500° C., for example, about 100° C. to about 400° C., about 100° C. to about 300° C., or about 100° C. to about 200° C.; a vacuum pressure of about 10−8 torr to about 10−3 torr, for example, about 10−8 torr to about 10−6 torr, about 10−8 torr to about 10−5 torr, or about 10−8 torr to about 10−4 torr; and a deposition rate of about 0.01 angstrom per second (Å/sec) to about 100 Å/sec, for example, about 0.01 Å/sec to about 80 Å/sec, about 0.01 Å/sec to about 60 Å/sec, about 0.01 Å/sec to about 40 Å/sec, about 0.01 Å/sec to about 20 Å/sec, about 0.01 Å/sec to about 10 Å/sec, or about 0.01 Å/sec to about 5 Å/sec. However, the deposition conditions are not limited thereto.
In an embodiment, when the hole injection layer is formed using spin coating, coating conditions may vary according to the material used to form the hole injection layer, and the structure and thermal properties of the hole injection layer. For example, a coating speed may be from about 2,000 revolutions per minute (rpm) to about 5,000 rpm, for example, about 2,000 rpm to about 4,000 rpm, about 2,000 rpm to about 3,000 rpm, or about 2,000 rpm to about 2,500 rpm, and a temperature at which a heat treatment is performed to remove a solvent after coating may be from about 80° C. to about 200° C., for example, about 80° C. to about 180° C., about 80° C. to about 160° C., about 80° C. to about 140° C., about 80° C. to about 120° C., or about 80° C. to about 100° C. However, the coating conditions are not limited thereto.
The conditions for forming the hole-transporting layer and the electron-blocking layer may be the same as the conditions for forming the hole injection layer.
The hole transport region may include at least one of m-MTDATA, TDATA, 2-TNATA, NPB, β-NPB, TPD, Spiro-TPD, Spiro-NPB, methylated NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA), polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphor sulfonic acid (PANI/CSA), polyaniline/poly(4-styrenesulfonate) (PANI/PSS), a compound represented by Formula 201, and a compound represented by Formula 202:
Wherein Ar101 and Ar102 in Formula 201 may each independently be:
a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an acenaphthylene group, a fluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, or a pentacenylene group; or
a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an acenaphthylene group, a fluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, or a pentacenylene group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkoxy group, a C1-C60 alkylthio group, a C3-C10 cycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkyl group, a C2-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a C1-C60 heteroaryloxy group, a C1-C60 heteroarylthio group, a C1-C60 heteroalkylaryl group, a monovalent non-aromatic condensed polycyclic group, or a monovalent non-aromatic condensed heteropolycyclic group.
xa and xb in Formula 201 may each independently be an integer from 0 to 5, or 0, 1, or 2. For example, xa may be 1 and xb may be 0, but xa and xb are not limited thereto.
R101 to R108, R111 to R119 and R121 to R124 in Formulae 201 and 202 may each independently be:
hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C1-C10 alkyl group (for example, a methyl group, an ethyl group, a propyl group, a butyl group, pentyl group, a hexyl group, etc.), a C1-C10 alkoxy group (for example, a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group, etc.) or a C1-C10 alkylthio group (for example, a thiomethyl group, an thioethyl group, a thiopropyl group, a thiobutyl group, thiopentyl group, a thiohexyl group, etc.);
a C1-C10 alkyl group, a C1-C10 alkylthio group, or a C1-C10 alkoxy group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof or a phosphoric acid group or a salt thereof;
a phenyl group, a naphthyl group, an anthracenyl group, a fluorenyl group, or a pyrenyl group; or
a phenyl group, a naphthyl group, an anthracenyl group, a fluorenyl group, and a pyrenyl group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C1-C10 alkyl group, a C1-C10 alkylthio group, or a C1-C10 alkoxy group,
but embodiments of the present disclosure are not limited thereto.
R109 in Formula 201 may be:
a phenyl group, a naphthyl group, an anthracenyl group, or a pyridinyl group; or
a phenyl group, a naphthyl group, an anthracenyl group, and a pyridinyl group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C1-C20 alkyl group, a C1-C20 alkoxy group, a C1-C20 alkylthio group, a phenyl group, a naphthyl group, an anthracenyl group, or a pyridinyl group.
According to an embodiment, the compound represented by Formula 201 may be represented by Formula 201A, but embodiments of the present disclosure are not limited thereto:
Wherein R101, R111, R112, and R109 in Formula 201A may be understood by referring to the description provided herein.
For example, the compound represented by Formula 201, and the compound represented by Formula 202 may include compounds HT1 to HT20 illustrated below, but are not limited thereto:
A thickness of the hole transport region may be in the range of about 100 Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å, about 100 Å to about 800 Å, about 200 Å to about 600 Å, or about 300 Å to about 400 Å. When the hole transport region includes all of a hole injection layer and a hole transport layer, a thickness of the hole injection layer may be in a range of about 100 Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å, about 100 Å to about 2,000 Å, about 200 Å to about 3,000 Å, about 300 Å to about 4,000 Å, about 400 Å to about 5,000 Å, about 500 Å to about 6,000 Å, about 600 Å to about 7,000 Å, or about 800 Å to about 9,000 Å, and a thickness of the hole transport layer may be in a range of about 50 Å to about 2,000 Å, for example, about 100 Å to about 1,500 Å, about 100 Å to about 1500 Å, about 400 Å to about 1,000 Å, or about 500 Å to about 900 Å. While not wishing to be bound by theory, it is understood that when the thicknesses of the hole-transporting region, the hole injection layer and the hole-transporting layer are within these ranges, satisfactory or improved hole-transporting characteristics may be obtained without a substantial increase in driving voltage.
The hole transport region may further include, in addition to these materials, a charge-generation material for the improvement of conductive properties. The charge-generation material may be homogeneously or non-homogeneously dispersed in the hole-transporting region.
The charge-generation material may be, for example, a p-dopant. The p-dopant may be one of a quinone derivative, a metal oxide, or a cyano group-containing compound, but embodiments of the present disclosure are not limited thereto. Non-limiting examples of the p-dopant are a quinone derivative, such as tetracyanoquinonedimethane (TCNQ) or 2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinonedimethane (F4-TCNQ); a metal oxide, such as a tungsten oxide or a molybdenium oxide; and a cyano group-containing compound, such as Compound HT-D1 or Compound HT-D2 below, but are not limited thereto.
The hole transport region may include a buffer layer.
In an embodiment, the buffer layer may compensate for an optical resonance distance according to a wavelength of light emitted from the emission layer, and thus, efficiency of a formed organic light-emitting device may be improved.
The hole transport region may further include an electron blocking layer. The electron blocking layer may include a suitable material available in the art, for example, mCP, but embodiments of the present disclosure are not limited thereto.
In an embodiment, an emission layer (EML) may be formed on the hole transport region by vacuum deposition, spin coating, casting, LB deposition, or the like. When the emission layer is formed by vacuum deposition or spin coating, the deposition or coating conditions may be similar to those applied in forming the hole injection layer although the deposition or coating conditions may vary according to a material that is used to form the emission layer.
When the organic light-emitting device is a full-color organic light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, and a blue emission layer. In one or more embodiments, due to a stacked structure including a red emission layer, a green emission layer, and/or a blue emission layer, the emission layer may emit white light.
The emission layer may include a host and a dopant, the dopant may include a heterocyclic compound represented by Formula 1-1 or 1-2, and the heterocyclic compound is the same as described in the present specification.
The host may include at least one of TPBi, TBADN, ADN (also referred to as “DNA”), CBP, CDBP, TCP, mCP, or Compound H50 to Compound H52:
In an embodiment, the host may further include a compound represented by Formula 301:
wherein Ar111 and Ar112 in Formula 301 may each independently be:
a phenylene group, a naphthylene group, a phenanthrenylene group, or a pyrenylene group; or
a phenylene group, a naphthylene group, a phenanthrenylene group, or a pyrenylene group, each independently substituted with at least one of a phenyl group, a naphthyl group, or an anthracenyl group.
Ar113 to Ar116 in Formula 301 may each independently be:
a C1-C10 alkyl group, a phenyl group, a naphthyl group, a phenanthrenyl group, or a pyrenyl group; or
a phenyl group, a naphthyl group, a phenanthrenyl group, or a pyrenyl group, each independently substituted with at least one of a phenyl group, a naphthyl group, or an anthracenyl group.
g, h, i, and j in Formula 301 may each independently be an integer from 0 to 4, and may be, for example, 0, 1, or 2.
Ar113 to Ar116 in Formula 301 may each independently be:
a C1-C10 alkyl group, substituted with at least one of a phenyl group, a naphthyl group, or an anthracenyl group;
a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl, a phenanthrenyl group, or a fluorenyl group;
a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, a phenanthrenyl group, or a fluorenyl group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkoxy group, a C1-C60 alkylthio group, a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group, a phenanthrenyl group, or a fluorenyl group; or
but embodiments of the present disclosure are not limited thereto.
In an embodiment, the host may include a compound represented by Formula 302 below:
wherein Ar122 to Ar125 in Formula 302 are the same as described in detail in connection with Ar113 in Formula 301.
Ar126 and Ar127 in Formula 302 may each independently be a C1-C10 alkyl group (for example, a methyl group, an ethyl group, or a propyl group).
k and l in Formula 302 may each independently be an integer from 0 to 4. For example, k and l may be 0, 1, or 2.
When the emission layer includes a host and a dopant, an amount of the dopant may be in a range of about 0.01 parts by weight to about 15 parts by weight based on 100 parts by weight of the host, for example, about 0.01 parts by weight to about 12 parts by weight, about 0.01 parts by weight to about 10 parts by weight, about 0.01 parts by weight to about 8 parts by weight, about 0.01 parts by weight to about 6 parts by weight, about 0.01 parts by weight to about 4 parts by weight, or about 0.01 parts by weight to about 2 parts by weight based on 100 parts by weight of the host, but embodiments of the present disclosure are not limited thereto.
A thickness of the emission layer may be in a range of about 100 Å to about 1,000 Å, for example, about 100 Å to about 800 Å, about 200 Å to about 600 Å, or about 300 Å to about 400 Å. While not wishing to be bound by theory, it is understood that when the thickness of the emission layer is within these ranges, excellent or improved light-emission characteristics may be obtained without a substantial increase in driving voltage.
Then, an electron transport region may be located on the emission layer.
The electron transport region may include at least one of a hole-blocking layer, an electron transport layer, or an electron injection layer.
For example, the electron transport region may have a hole blocking layer/electron transport layer/electron injection layer structure or an electron transport layer/electron injection layer structure, and the structure of the electron transport region is not limited thereto. The electron-transporting layer may have a single-layered structure or a multi-layered structure including two or more different materials.
Conditions for forming the hole blocking layer, the electron transport layer, and the electron injection layer which constitute the electron transport region may be understood by referring to the conditions for forming the hole injection layer.
When the electron transport region includes a hole blocking layer, the hole blocking layer may include, for example, at least one of BCP and Bphen, but embodiments of the present disclosure are not limited thereto.
A thickness of the hole-blocking layer may be in a range of about 20 Å to about 1,000 Å, for example, about 10 Å to about 100 Å, about 20 Å to about 200 Å, about 30 Å to about 300 Å, about 40 Å to about 400 Å, about 50 Å to about 500 Å, about 60 Å to about 600 Å, about 70 Å to about 700 Å, about 80 Å to about 800 Å, about 90 Å to about 900 Å, or about 100 Å to about 1000 Å. While not wishing to be bound by theory, it is understood that when the thickness of the hole-blocking layer is within these ranges, excellent or improved hole-blocking characteristics can be obtained without a substantial increase in driving voltage.
The electron transport layer may further include at least one of BCP, Bphen, Alq3, BAlq, TAZ, or NTAZ.
In an embodiment, the electron transport layer may include at least one of ET1 to ET25, but are not limited thereto:
A thickness of the electron-transporting layer may be in the range of about 100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å, about 200 Å to about 600 Å, about 250 Å to about 700 Å, about 300 Å to about 800 Å, about 350 Å to about 900 Å, or about 400 Å to about 1000 Å. While not wishing to be bound by theory, it is understood that when the thickness of the electron-transporting layer is within the range described above, the electron-transporting layer may have satisfactory or improved electron-transporting characteristics without a substantial increase in driving voltage.
The electron-transporting layer may include a metal-containing material in addition to the material as described above.
The metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1 (lithium quinolate, LiQ) or ET-D2:
The electron transport region may include an electron injection layer (EIL) that promotes the flow of electrons from the second electrode 19 thereinto.
The electron injection layer may include at least one of LiF, NaCl, CsF, Li2O, or BaO.
A thickness of the electron injection layer may be in a range of about 1 Å to about 100 Å, and, for example, about 3 Å to about 90 Å, about 6 Å to about 80 Å, about 9 Å to about 70 Å, about 12 Å to about 60 Å, about 15 Å to about 50 Å, about 18 Å to about 40 Å, or about 20 Å to about 30 Å. While not wishing to be bound by theory, it is understood that when the thickness of the electron injection layer is within the range described above, the electron injection layer may have satisfactory or improved electron injection characteristics without a substantial increase in driving voltage.
The second electrode 19 is located on the organic layer 15. The second electrode 19 may be a cathode. A material for forming the second electrode 19 may be metal, an alloy, an electrically conductive compound, or a combination thereof, which have a relatively low work function. For example, lithium (Li), magnesium (Mg), aluminum (AI), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), or magnesium-silver (Mg—Ag) may be used as the material for forming the second electrode 19. In an embodiment, to manufacture a top-emission type light-emitting device, a transmissive electrode formed using ITO or IZO may be used as the second electrode 19.
Hereinbefore, the organic light-emitting device has been described with reference to
In the present specification, the C5-C30 carbocyclic group refers to an aromatic or non-aromatic mono or polycyclic group having 1 to 30 carbon atoms. The C1-C30 heterocyclic group refers to an aromatic or non-aromatic mono or polycyclic group having 1 to 30 carbon atoms which includes at least one heteroatom N, O, P, Si, B, Se, or S as a ring-forming atom.
The term “C1-C60 alkyl group” as used herein refers to a linear or branched aliphatic saturated hydrocarbon monovalent group having 1 to 60 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an isoamyl group, and a hexyl group.
The term “C1-C60 alkylene group” as used herein refers to a divalent group having the same structure as the C1-C60 alkyl group.
The term “C1-C60 alkoxy group” used herein refers to a monovalent group represented by —OA101 (wherein A101 is the C1-C60 alkyl group), and examples thereof include a methoxy group, an ethoxy group, and an isopropyloxy group.
The term “C1-C60 alkylthio group” used herein refers to a monovalent group represented by —SA108 (wherein A101 is the C1-C60 alkyl group), and examples thereof include a thiomethyl group, a thioethyl group, and a thioisopropyl group.
The term “C2-C60 alkenyl group” as used herein refers to a hydrocarbon group formed by substituting at least one carbon-carbon double bond in the middle or at the terminus of the C2-C60 alkyl group, and examples thereof include an ethenyl group, a propenyl group, and a butenyl group. The term “C2-C60 alkenylene group” as used herein refers to a divalent group having the same structure as the C2-C60 alkenyl group.
The term “C2-C60 alkynyl group” as used herein refers to a hydrocarbon group formed by substituting at least one carbon-carbon triple bond in the middle or at the terminus of the C2-C60 alkyl group, and examples thereof include an ethynyl group, and a propynyl group. The term “C2-C60 alkynylene group” as used herein refers to a divalent group having the same structure as the C2-C60 alkynyl group.
The term “C3-C10 cycloalkyl group” as used herein refers to a monovalent saturated hydrocarbon monocyclic group having 3 to 10 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group. The term “C3-C10 cycloalkylene group” as used herein refers to a divalent group having the same structure as the C3-C10 cycloalkyl group.
The term “C1-C10 heterocycloalkyl group” as used herein refers to a monovalent saturated monocyclic group having at least one heteroatom N, O, P, Si, B, Se, or S as a ring-forming atom and 1 to 10 carbon atoms, and examples thereof include a tetrahydrofuranyl group and a tetrahydrothiophenyl group. The term “C2-C10 heterocycloalkylene group” as used herein refers to a divalent group having the same structure as the C1-C10 heterocycloalkyl group.
The term C3-C10 cycloalkenyl group used herein refers to a monovalent monocyclic group that has 3 to 10 carbon atoms and at least one carbon-carbon double bond in the ring thereof and no aromaticity, and examples thereof include a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. The term “C3-C10 cycloalkenylene group” as used herein refers to a divalent group having the same structure as the C3-C10 cycloalkenyl group.
The term “C2-C10 heterocycloalkenyl group” as used herein refers to a monovalent monocyclic group that has at least one hetero atom N, O, P, Si, B, Se, or S as a ring-forming atom, 2 to 10 carbon atoms, and at least one carbon-carbon double bond in its ring. Examples of the C2-C10 heterocycloalkenyl group are a 2,3-hydrofuranyl group, and a 2,3-hydrothiophenyl group. The term “C2-C10 heterocycloalkenylene group” as used herein refers to a divalent group having the same structure as the C2-C10 heterocycloalkenyl group.
The term “C6-C60 aryl group” as used herein refers to a monovalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms, and the term “C6-C60 arylene group” as used herein refers to a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. Examples of the C6-C60 aryl group include a phenyl group or a benzene group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, and a chrysenyl group. For example, a “benzene group” may be a benzo group, a phenyl group, a phenylene group, or the like, and this may be understood by one of ordinary skill in the art, depending on the structure of the formula including the “benzene group”. When the C6-C60 aryl group and the C6-C60 arylene group each include two or more rings, the rings may be fused to each other.
The term “C7-C60 alkylaryl group” as used herein refers to a C6-C59 aryl group substituted with at least one C1-C54 alkyl or alkylene group.
The term “C1-C60 heteroaryl group” as used herein refers to a monovalent group having a cyclic aromatic system having at least one heteroatom N, O, P, Si, B, Se, or S as a ring-forming atom and a carbocyclic aromatic system having 1 to 60 carbon atoms, and the term “C1-C60 heteroarylene group” as used herein refers to a divalent group having a cyclic aromatic system having at least one hetero atom N, O, P, Si, B, Se, or S as a ring-forming atom and a carbocyclic aromatic system having 1 to 60 carbon atoms. Examples of the C2-C60 heteroaryl group include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, and an isoquinolinyl group.
When the C1-C60 heteroaryl group and the C1-C60 heteroarylene group each include two or more rings, the rings may be fused to each other.
The term “C6-C60 aryloxy group” as used herein indicates —OA102 (wherein A102 is the C6-C60 aryl group), and the term “C6-C60 arylthio group” as used herein indicates —SA103 (wherein A103 is the C6-C60 aryl group).
The “C7-C60 arylalkyl group” as used herein refers to -A104A105 (where A104 is a C1-C54 alkyl group, and A105 is a C6-C59 aryl group), and includes, for example, a cumyl group.
The “C2-C60 heteroarylalkyl group” as used herein refers to -A106A107 (where A106 is a C1-C59 alkyl group, and A107 is a C1-C59 heteroaryl group).
The term “C1-C60 heteroaryloxy group” as used herein refers to —OA109 (wherein A109 is the C1-C6 heteroaryl group), the term “C1-C60 heteroarylthio group” as used herein indicates —SA110 (wherein A110 is the C1-C60 heteroaryl group), and the term “C1-C60 heteroalkylaryl group” as used herein refers to -A111A112 (A111 is a C1-C55 heteroalkylene or heteroalkyl group, and A112 is a C1-C59 heteroaryl group).
The term “monovalent non-aromatic condensed polycyclic group” as used herein refers to a monovalent group in which two or more rings are condensed with each other, only carbon is used as a ring-forming atom (for example, the number of carbon atoms may be 8 to 60) and the whole molecule is a non-aromaticity group. Examples of the monovalent non-aromatic condensed polycyclic group include a fluorenyl group. The term “divalent non-aromatic condensed polycyclic group” as used herein refers to a divalent group having the same structure as a monovalent non-aromatic condensed polycyclic group.
The term “monovalent non-aromatic condensed heteropolycyclic group” as used herein refers to a monovalent group having two or more rings condensed to each other, a heteroatom N, O, P, Si, B, Se, or S, other than carbon atoms (for example, having 2 to 60 carbon atoms), as a ring-forming atom, and no aromaticity in its entire molecular structure. Examples of the monovalent non-aromatic condensed heteropolycyclic group include a carbazolyl group. The term “divalent non-aromatic heterocondensed polycyclic group” as used herein refers to a divalent group having the same structure as a monovalent non-aromatic heterocondensed polycyclic group.
At least one substituent of the substituted C5-C30 carbocyclic group, the substituted C1-C30 heterocyclic group, the substituted C1-C60 alkyl group, the substituted C2-C60 alkenyl group, the substituted C2-C60 alkynyl group, the substituted C1-C60 alkoxy group, the substituted C1-C60 alkylthio group, the substituted C3-C10 cycloalkyl group, the substituted C1-C10 heterocycloalkyl group, the substituted C3-C10 cycloalkenyl group, the substituted C2-C10 heterocycloalkenyl group, the substituted C6-C60 aryl group, the substituted C7-C60 arylalkyl group, the substituted C6-C60 aryloxy group, the substituted C6-C60 arylthio group, the substituted C1-C60 heteroaryl group, the substituted C1-C60 heteroaryloxy group, the substituted C1-C60 heteroarylthio group, the substituted C2-C60 heteroarylalkyl group, the substituted monovalent non-aromatic condensed polycyclic group, or the substituted monovalent non-aromatic condensed heteropolycyclic group may be:
deuterium, —F, —Cl, —Br, —I, —CD3, —CD2H, —CDH2, —CF3, —CF2H, —CFH2, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkylthio group, or a C1-C60 alkoxy group;
a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkylthio group, or a C1-C60 alkoxy group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, —CD3, —CD2H, —CDH2, —CF3, —CF2H, —CFH2, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C2-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C7-C60 arylalkyl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a C1-C60 heteroaryloxy group, a C1-C60 heteroarylthio group, a C2-C60 heteroarylalkyl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —Si(Q11)(Q12)(Q13), —N(Q14)(Q15), —B(Q16)(Q17), or —P(═O)(Q18)(Q19);
a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C2-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C7-C60 arylalkyl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C7-C60 alkylaryl group, a C1-C60 heteroaryl group, a C1-C60 heteroaryloxy group, a C1-C60 heteroarylthio group, a C2-C60 heteroarylalkyl group, a monovalent non-aromatic condensed polycyclic group, or a monovalent non-aromatic condensed heteropolycyclic group;
a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C2-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C7-C60 arylalkyl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a C1-C60 heteroaryloxy group, a C1-C60 heteroarylthio group, a C2-C60 heteroarylalkyl group, a monovalent non-aromatic condensed polycyclic group, or a monovalent non-aromatic condensed heteropolycyclic group, each independently substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkoxy group, a C1-C60 alkylthio group, a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C2-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C7-C60 arylalkyl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a C1-C60 heteroaryloxy group, a C1-C60 heteroarylthio group, a C2-C60 heteroarylalkyl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —Si(Q21)(Q22)(Q23), —N(Q24)(Q25), —B(Q26)(Q27), or —P(═O)(Q28)(Q29), or
—Si(Q31)(Q32)(Q33), —N(Q34)(Q35), —B(Q36)(Q37), or —P(═O)(Q38)(Q39),
wherein Q1 to Q9, Q11 to Q19, Q21 to Q29, and Q31 to Q39 may each independently be hydrogen, a substituted or unsubstituted C1-C60 alkyl group, a substituted or unsubstituted C2-60 alkenyl group, a substituted or unsubstituted C2-C60 alkynyl group, a substituted or unsubstituted C1-C60 alkoxy group, a substituted or unsubstituted C1-C60 alkylthio group, a substituted or unsubstituted C3-C10 cycloalkyl group, a substituted or unsubstituted C1-C10 heterocycloalkyl group, a substituted or unsubstituted C3-C10 cycloalkenyl group, a substituted or unsubstituted C2-C10 heterocycloalkenyl group, a substituted or unsubstituted C6-C60 aryl group, a substituted or unsubstituted C7-C60 arylalkyl group, a substituted or unsubstituted C6-C60 aryloxy group, a substituted or unsubstituted C6-C60 arylthio group, a substituted or unsubstituted C1-C60 heteroaryl group, a substituted or unsubstituted C1-C60 heteroaryloxy group, a substituted or unsubstituted C1-C60 heteroarylthio group, a substituted or unsubstituted C2-C60 heteroarylalkyl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, or a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group.
The term “room temperature” used herein refers to a temperature of about 25° C.
The terms “a biphenyl group” and “a terphenyl group” as used herein refer to a monovalent group in which two or three benzene groups are bonded to each other through a single bond.
Hereinafter, a compound and an organic light-emitting device according to embodiments are described in detail with reference to Synthesis Example and Examples. However, the organic light-emitting device is not limited thereto. The wording “B was used instead of A” used in describing Synthesis Examples means that an amount of A used was identical to an amount of B used, in terms of a molar equivalent.
KOtBu (potassium tert-butoxide, 9.01 grams (g), 128 millimole (mmol)) was loaded into a reaction vessel and charged with nitrogen. 80 milliliter (mL) of methanol and tert-butylcarbamidine hydrochloride (5.76 g, 42 mmol) were added thereto and then dissolved at room temperature. 15 minutes after, dimethyl chloromalonate (6.8 mL, 42 mmol) was additionally added to the reaction vessel to cause a reaction, followed by stirring for 4 hours at a temperature of 65° C. After the reaction was completed, the resultant mixture was cooled to room temperature, followed by primary extraction using diethyl ether and water, and secondary extraction using methylchoride (MC) and HBr. Finally, the organic layer obtained after removing the remaining salt therefrom by using an aqueous sodium hydroxide solution was dried using anhydrous magnesium sulfate (MgSO4) and concentrated. Without further purification, the resulting yellow solid was mixed with POCl3 (20 mL) and reacted at a temperature of 120° C. for 15 hours. After the reaction was completed, the resultant mixture was washed with an aqueous sodium hydroxide solution and an aqueous sodium hydrogen carbonate solution. An extraction process was performed thereon by using MC and water, and the obtained organic layer was filtered through a filter and concentrated. The solid compound obtained therefrom was directly used in the next reaction without further purification.
LC-Mass (calculated: 237.98 g/mol, found: 238.9 g/mol (M+1)) Synthesis of Intermediate 1(b)
Intermediate 1(a) (2.0 g, 8.2 mmol), bis(4-tert-butyl)phenyl)amine (5.2 g, 18.4 mmol), Pd2(dba)3 (Tris(dibenzylideneacetone)dipalladium(0), 0.38 g, 0.41 mmol), SPhos (([2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl, 0.36 g, 0.85 mmol), and NaOtBu (sodium tert-butoxide, 1.95 g, 20.6 mmol) were added to a reaction vessel and dissolved in 80 mL of toluene, and stirred at a temperature of 110° C. After completion of the reaction, the reaction solution was cooled to room temperature, and then the obtained organic layer was filtered and concentrated using a Celite pad. The solid compound obtained therefrom was separated by column chromatography (hexane/ethylacetate 12%). The resulting pale yellow solid was obtained with a yield of 1.44 g (24%).
LC-Mass (calculated: 728.46 g/mol, found: 729.4 g/mol (M+1))
Intermediate 1(b) (0.47 g, 0.64 mmol) was loaded in a reaction vessel which was able to be vacuumed, and was charged three times with vacuum and nitrogen. While the temperature of the reaction vessel was maintained at a temperature of −78° C. by using dry ice, tert-Butyl benzene (9.5 mL) was added thereto. tert-butyl lithium (1.47 molar (M) in pentane, 1.2 mL, 1.76 mmol) was added to the reaction vessel and reacted at a temperature of −60° C. for 1 hour. The temperature was adjusted to be −78° C., and then, 0.20 mL (2.07 mmol) of BBr3 was added thereto. The temperature was gradually increased to room temperature, and then, N,N-diisopropylethylamine (0.40 mL, 2.29 mmol) was added thereto. The mixture of the reaction vessel was reacted at a temperature of 110° C. for 15 hours. After completion of the reaction, the reaction solution was cooled to room temperature, and then the obtained organic layer was filtered and concentrated using a Florisil® pad. The solid compound obtained therefrom was separated by column chromatography (hexane/MC). The resulting pale yellow solid was obtained with a yield of 0.04 g (10%).
LC-Mass (calculated: 702.48 g/mol, found: 703.4 g/mol (M+1))
Carbazole (4.36 g, 26 mmol) was loaded in a reaction vessel which was able to be vacuumed, and was charged three times with vacuum and nitrogen. NaH (60% in oil, 1.03 g, 26 mmol) was dissolved in 30 mL of DMF (dimethylformamide) and then loaded in the reaction vessel. After stirring at room temperature for 30 minutes, fenclorim (1.92 g, 8.6 mmol) was added thereto and then reacted at a temperature of 120° C. for 3 hours. After completion of the reaction, a precipitation process was performed thereon using water and then, an extraction process was performed thereon using methylchloride (MC), and the solvent of the obtained organic layer was dried with anhydrous magnesium sulfate (MgSO4) and concentrated. The solid compound obtained therefrom was separated by column chromatography (hexane/EA, 12%) to obtain Intermediate 3(a) with a yield of 0.45 g (11%).
LC-Mass (calculated: 486.18 g/mol, found: 487.2 g/mol (M+1)) Synthesis of Compound 3
Intermediate 3(a) (0.17 g, 0.35 mmol) was loaded in a reaction vessel which was able to be vacuumed, and was charged three times with vacuum and nitrogen. 4 mL of o-dichlorobenzene and 0.08 mL of BBr3 were loaded into the reaction vessel at room temperature, and reacted at a temperature of 140° C. for 15 hours. After completion of the reaction, diisopropylethylamine (0.40 mL, 2.29 mmol) was added at a temperature of 0° C. using ice. After two hours of stirring at room temperature, an organic layer was separated therefrom using an organic solvent, and then the solvent of the obtained organic layer was dried using anhydrous magnesium sulfate (MgSO4) and concentrated. The solid compound obtained therefrom was separated by column chromatography (hexane/MC).
As a result, pale yellow solid was obtained.
LC-Mass (calculated: 494.17 g/mol, found: 495.2 g/mol (M+1))
Measurements were made according to the method as below. Results thereof are shown in Table 26.
From Table 26, it can be confirmed that the heterocyclic compound represented by Formula 1 has a material skeleton that is advantageous for blue due to the shift to a shorter wavelength caused by pyrimidine.
HOMO energy level, LUMO energy level, energy gap, T1 energy level, S1 energy level, gap between S1 and T1, and Oscillator strength of some of the heterocyclic compounds represented by Formula 1-1 or 1-2 was evaluated using the Gaussian 09 program accompanying molecular structure optimization by density functional theory (DFT) based on B3LYP, and the results are shown in Table 27 below.
In the case of Compound A, the HOMO level is too high to cause a problem with the electron transport, and in Compound B, D, and E, the oscillator strength is low and thus the luminous efficiency is low. In the case of Compound D, the triplet energy is particularly low, and the efficiency characteristics are considered to be very low. In the case of Compound C, DEST is 0.7 eV or more and thus it is not able to utilize the triplet energy by the reverse intersystem crossing and the internal quantum efficiency will be less than about 25%, and due to the structure it is expected to hardly express high efficiency in deep blue. In the calculation results of Compounds 1 and 3 performed to compensate for the disadvantages of the above compound A to E, the characteristics of luminous efficiency are increased by increasing the oscillator strength (f) value, and the triplet energy is maximized by maintaining the gap between the triplet energy and the singlet energy for the reverse intersystem crossing. By designing to have a specific material structure, it can be expected to improve the stability of the material while having high-efficiency emission characteristics in blue
An organic light-emitting device containing the heterocyclic compound can have high or improved efficiency, long or improved lifespan, low driving voltage and high or improved color purity.
It should be understood that embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. While one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the following claims.
An organic light-emitting device containing the heterocyclic compound can have high or improved efficiency, long or improved lifespan, low driving voltage and high or improved color purity.
It should be understood that embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. While one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present detailed description as defined by the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2020-0056667 | May 2020 | KR | national |
| 10-2021-0060729 | May 2021 | KR | national |
