Patent Grant
12103942
The present disclosure generally relates to organometallic compounds and formulations and their various uses including as emitters in devices such as organic light emitting diodes and related electronic devices.
Opto-electronic devices that make use of organic materials are becoming increasingly desirable for various reasons. Many of the materials used to make such devices are relatively inexpensive, so organic opto-electronic devices have the potential for cost advantages over inorganic devices. In addition, the inherent properties of organic materials, such as their flexibility, may make them well suited for particular applications such as fabrication on a flexible substrate. Examples of organic opto-electronic devices include organic light emitting diodes/devices (OLEDs), organic phototransistors, organic photovoltaic cells, and organic photodetectors. For OLEDs, the organic materials may have performance advantages over conventional materials.
OLEDs make use of thin organic films that emit light when voltage is applied across the device. OLEDs are becoming an increasingly interesting technology for use in applications such as flat panel displays, illumination, and backlighting.
One application for phosphorescent emissive molecules is a full color display. Industry standards for such a display call for pixels adapted to emit particular colors, referred to as “saturated” colors. In particular, these standards call for saturated red, green, and blue pixels. Alternatively, the OLED can be designed to emit white light. In conventional liquid crystal displays emission from a white backlight is filtered using absorption filters to produce red, green and blue emission. The same technique can also be used with OLEDs. The white OLED can be either a single emissive layer (EML) device or a stack structure. Color may be measured using CIE coordinates, which are well known to the art.
Fluorinated alkyl groups are widely incorporated in OLED ligands to adjust color and efficiency of electroluminescent devices. The present disclosure provides 9,9-difluoro-9H-fluorene, 9,9-difluoro-10,10-dimethyl-9,10-dihydrophenanthrene, 9,9,10,10-tetrafluoro-9,10-dihydrophenanthrene and analogs that when used as emitters in OLEDs provide more opportunities for fine-tuning the emission wavelength and improve stability of the OLEDs.
In one aspect, the present disclosure provides a compound comprising a metal M and a first ligand LA comprising the structure of
where the compound is capable of functioning as a phosphorescent emitter in an organic light emitting device at room temperature; where, ring A and ring B are each independently a 5-membered or 6-membered carbocyclic or heterocyclic ring; Z1 and Z2 are each independently selected from the group consisting of a direct bond, CR1R2 and CR1R2CR3R4; no more than one of Z1 and Z2 is a direct bond; RA and RB each represent mono to the maximum allowable substitutions, or no substitution; each RA, RB, R1, R2, R3, and R4 is independently a hydrogen or a substituent selected from the group consisting of the general substituents defined herein; at least one of R1, R2, R3, and R4 is a fluorine atom; and any two substituents can be joined or fused to form a ring.
In another aspect, the present disclosure provides a formulation of the compound of the present disclosure.
In yet another aspect, the present disclosure provides an OLED having an organic layer comprising the compound of the present disclosure.
In yet another aspect, the present disclosure provides a consumer product comprising an OLED with an organic layer comprising the compound of the present disclosure.
A. Terminology
Unless otherwise specified, the below terms used herein are defined as follows:
As used herein, the term “organic” includes polymeric materials as well as small molecule organic materials that may be used to fabricate organic opto-electronic devices. “Small molecule” refers to any organic material that is not a polymer, and “small molecules” may actually be quite large. Small molecules may include repeat units in some circumstances. For example, using a long chain alkyl group as a substituent does not remove a molecule from the “small molecule” class. Small molecules may also be incorporated into polymers, for example as a pendent group on a polymer backbone or as a part of the backbone. Small molecules may also serve as the core moiety of a dendrimer, which consists of a series of chemical shells built on the core moiety. The core moiety of a dendrimer may be a fluorescent or phosphorescent small molecule emitter. A dendrimer may be a “small molecule,” and it is believed that all dendrimers currently used in the field of OLEDs are small molecules.
As used herein, “top” means furthest away from the substrate, while “bottom” means closest to the substrate. Where a first layer is described as “disposed over” a second layer, the first layer is disposed further away from substrate. There may be other layers between the first and second layer, unless it is specified that the first layer is “in contact with” the second layer. For example, a cathode may be described as “disposed over” an anode, even though there are various organic layers in between.
As used herein, “solution processable” means capable of being dissolved, dispersed, or transported in and/or deposited from a liquid medium, either in solution or suspension form.
A ligand may be referred to as “photoactive” when it is believed that the ligand directly contributes to the photoactive properties of an emissive material. A ligand may be referred to as “ancillary” when it is believed that the ligand does not contribute to the photoactive properties of an emissive material, although an ancillary ligand may alter the properties of a photoactive ligand.
As used herein, and as would be generally understood by one skilled in the art, a first “Highest Occupied Molecular Orbital” (HOMO) or “Lowest Unoccupied Molecular Orbital” (LUMO) energy level is “greater than” or “higher than” a second HOMO or LUMO energy level if the first energy level is closer to the vacuum energy level. Since ionization potentials (IP) are measured as a negative energy relative to a vacuum level, a higher HOMO energy level corresponds to an IP having a smaller absolute value (an IP that is less negative). Similarly, a higher LUMO energy level corresponds to an electron affinity (EA) having a smaller absolute value (an EA that is less negative). On a conventional energy level diagram, with the vacuum level at the top, the LUMO energy level of a material is higher than the HOMO energy level of the same material. A “higher” HOMO or LUMO energy level appears closer to the top of such a diagram than a “lower” HOMO or LUMO energy level.
As used herein, and as would be generally understood by one skilled in the art, a first work function is “greater than” or “higher than” a second work function if the first work function has a higher absolute value. Because work functions are generally measured as negative numbers relative to vacuum level, this means that a “higher” work function is more negative. On a conventional energy level diagram, with the vacuum level at the top, a “higher” work function is illustrated as further away from the vacuum level in the downward direction. Thus, the definitions of HOMO and LUMO energy levels follow a different convention than work functions.
The terms “halo,” “halogen,” and “halide” are used interchangeably and refer to fluorine, chlorine, bromine, and iodine.
The term “acyl” refers to a substituted carbonyl radical (C(O)—Rs).
The term “ester” refers to a substituted oxycarbonyl (—O—C(O)—Rs or —C(O)—O—Rs) radical.
The term “ether” refers to an —ORs radical.
The terms “sulfanyl” or “thio-ether” are used interchangeably and refer to a —SR, radical.
The term “sulfinyl” refers to a —S(O)—Rs radical.
The term “sulfonyl” refers to a —SO2—Rs radical.
The term “phosphino” refers to a —P(Rs)3 radical, wherein each Rs can be same or different.
The term “silyl” refers to a —Si(Rs)3 radical, wherein each Rs can be same or different.
The term “boryl” refers to a —B(Rs)2 radical or its Lewis adduct —B(Rs)3 radical, wherein Rs can be same or different.
In each of the above, Rs can be hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, and combination thereof. Preferred Rs is selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, and combination thereof.
The term “alkyl” refers to and includes both straight and branched chain alkyl radicals. Preferred alkyl groups are those containing from one to fifteen carbon atoms and includes methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, and the like. Additionally, the alkyl group may be optionally substituted.
The term “cycloalkyl” refers to and includes monocyclic, polycyclic, and spiro alkyl radicals. Preferred cycloalkyl groups are those containing 3 to 12 ring carbon atoms and includes cyclopropyl, cyclopentyl, cyclohexyl, bicyclo[3.1.1]heptyl, spiro[4.5]decyl, spiro[5.5]undecyl, adamantyl, and the like. Additionally, the cycloalkyl group may be optionally substituted.
The terms “heteroalkyl” or “heterocycloalkyl” refer to an alkyl or a cycloalkyl radical, respectively, having at least one carbon atom replaced by a heteroatom. Optionally the at least one heteroatom is selected from O, S, N, P, B, Si and Se, preferably, O, S or N. Additionally, the heteroalkyl or heterocycloalkyl group may be optionally substituted.
The term “alkenyl” refers to and includes both straight and branched chain alkene radicals. Alkenyl groups are essentially alkyl groups that include at least one carbon-carbon double bond in the alkyl chain. Cycloalkenyl groups are essentially cycloalkyl groups that include at least one carbon-carbon double bond in the cycloalkyl ring. The term “heteroalkenyl” as used herein refers to an alkenyl radical having at least one carbon atom replaced by a heteroatom. Optionally the at least one heteroatom is selected from O, S, N, P, B, Si, and Se, preferably, O, S, or N. Preferred alkenyl, cycloalkenyl, or heteroalkenyl groups are those containing two to fifteen carbon atoms. Additionally, the alkenyl, cycloalkenyl, or heteroalkenyl group may be optionally substituted.
The term “alkynyl” refers to and includes both straight and branched chain alkyne radicals. Alkynyl groups are essentially alkyl groups that include at least one carbon-carbon triple bond in the alkyl chain. Preferred alkynyl groups are those containing two to fifteen carbon atoms. Additionally, the alkynyl group may be optionally substituted.
The terms “aralkyl” or “arylalkyl” are used interchangeably and refer to an alkyl group that is substituted with an aryl group. Additionally, the aralkyl group may be optionally substituted.
The term “heterocyclic group” refers to and includes aromatic and non-aromatic cyclic radicals containing at least one heteroatom. Optionally the at least one heteroatom is selected from O, S, N, P, B, Si, and Se, preferably, O, S, or N. Hetero-aromatic cyclic radicals may be used interchangeably with heteroaryl. Preferred hetero-non-aromatic cyclic groups are those containing 3 to 7 ring atoms which includes at least one hetero atom, and includes cyclic amines such as morpholino, piperidino, pyrrolidino, and the like, and cyclic ethers/thio-ethers, such as tetrahydrofuran, tetrahydropyran, tetrahydrothiophene, and the like. Additionally, the heterocyclic group may be optionally substituted.
The term “aryl” refers to and includes both single-ring aromatic hydrocarbyl groups and polycyclic aromatic ring systems. The polycyclic rings may have two or more rings in which two carbons are common to two adjoining rings (the rings are “fused”) wherein at least one of the rings is an aromatic hydrocarbyl group, e.g., the other rings can be cycloalkyls, cycloalkenyls, aryl, heterocycles, and/or heteroaryls. Preferred aryl groups are those containing six to thirty carbon atoms, preferably six to twenty carbon atoms, more preferably six to twelve carbon atoms. Especially preferred is an aryl group having six carbons, ten carbons or twelve carbons. Suitable aryl groups include phenyl, biphenyl, triphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, and azulene, preferably phenyl, biphenyl, triphenyl, triphenylene, fluorene, and naphthalene. Additionally, the aryl group may be optionally substituted.
The term “heteroaryl” refers to and includes both single-ring aromatic groups and polycyclic aromatic ring systems that include at least one heteroatom. The heteroatoms include, but are not limited to O, S, N, P, B, Si, and Se. In many instances, O, S, or N are the preferred heteroatoms. Hetero-single ring aromatic systems are preferably single rings with 5 or 6 ring atoms, and the ring can have from one to six heteroatoms. The hetero-polycyclic ring systems can have two or more rings in which two atoms are common to two adjoining rings (the rings are “fused”) wherein at least one of the rings is a heteroaryl, e.g., the other rings can be cycloalkyls, cycloalkenyls, aryl, heterocycles, and/or heteroaryls. The hetero-polycyclic aromatic ring systems can have from one to six heteroatoms per ring of the polycyclic aromatic ring system. Preferred heteroaryl groups are those containing three to thirty carbon atoms, preferably three to twenty carbon atoms, more preferably three to twelve carbon atoms. Suitable heteroaryl groups include dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, pyrrolodipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indoxazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, xanthene, acridine, phenazine, phenothiazine, phenoxazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenodipyridine, preferably dibenzothiophene, dibenzofuran, dibenzoselenophene, carbazole, indolocarbazole, imidazole, pyridine, triazine, benzimidazole, 1,2-azaborine, 1,3-azaborine, 1,4-azaborine, borazine, and aza-analogs thereof. Additionally, the heteroaryl group may be optionally substituted.
Of the aryl and heteroaryl groups listed above, the groups of triphenylene, naphthalene, anthracene, dibenzothiophene, dibenzofuran, dibenzoselenophene, carbazole, indolocarbazole, imidazole, pyridine, pyrazine, pyrimidine, triazine, and benzimidazole, and the respective aza-analogs of each thereof are of particular interest.
The terms alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aralkyl, heterocyclic group, aryl, and heteroaryl, as used herein, are independently unsubstituted, or independently substituted, with one or more general substituents.
In many instances, the general substituents are selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, boryl, and combinations thereof.
In some instances, the preferred general substituents are selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, heteroalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, sulfanyl, boryl, and combinations thereof.
In some instances, the more preferred general substituents are selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, alkoxy, aryloxy, amino, silyl, boryl, aryl, heteroaryl, sulfanyl, and combinations thereof.
In yet other instances, the most preferred general substituents are selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, aryl, heteroaryl, and combinations thereof.
The terms “substituted” and “substitution” refer to a substituent other than H that is bonded to the relevant position, e.g., a carbon or nitrogen. For example, when R represents mono-substitution, then one R1 must be other than H (i.e., a substitution). Similarly, when R represents di-substitution, then two of R1 must be other than H. Similarly, when R represents zero or no substitution, R1, for example, can be a hydrogen for available valencies of ring atoms, as in carbon atoms for benzene and the nitrogen atom in pyrrole, or simply represents nothing for ring atoms with fully filled valencies, e.g., the nitrogen atom in pyridine. The maximum number of substitutions possible in a ring structure will depend on the total number of available valencies in the ring atoms.
As used herein, “combinations thereof” indicates that one or more members of the applicable list are combined to form a known or chemically stable arrangement that one of ordinary skill in the art can envision from the applicable list. For example, an alkyl and deuterium can be combined to form a partial or fully deuterated alkyl group; a halogen and alkyl can be combined to form a halogenated alkyl substituent; and a halogen, alkyl, and aryl can be combined to form a halogenated arylalkyl. In one instance, the term substitution includes a combination of two to four of the listed groups. In another instance, the term substitution includes a combination of two to three groups. In yet another instance, the term substitution includes a combination of two groups. Preferred combinations of substituent groups are those that contain up to fifty atoms that are not hydrogen or deuterium, or those which include up to forty atoms that are not hydrogen or deuterium, or those that include up to thirty atoms that are not hydrogen or deuterium. In many instances, a preferred combination of substituent groups will include up to twenty atoms that are not hydrogen or deuterium.
The “aza” designation in the fragments described herein, i.e. aza-dibenzofuran, aza-dibenzothiophene, etc. means that one or more of the C—H groups in the respective aromatic ring can be replaced by a nitrogen atom, for example, and without any limitation, azatriphenylene encompasses both dibenzo[f,h]quinoxaline and dibenzo[f,h]quinoline. One of ordinary skill in the art can readily envision other nitrogen analogs of the aza-derivatives described above, and all such analogs are intended to be encompassed by the terms as set forth herein.
As used herein, “deuterium” refers to an isotope of hydrogen. Deuterated compounds can be readily prepared using methods known in the art. For example, U.S. Pat. No. 8,557,400, Patent Pub. No. WO 2006/095951, and U.S. Pat. Application Pub. No. US 2011/0037057, which are hereby incorporated by reference in their entireties, describe the making of deuterium-substituted organometallic complexes. Further reference is made to Ming Yan, et al., Tetrahedron 2015, 71, 1425-30 and Atzrodt et al., Angew. Chem. Int. Ed. (Reviews) 2007, 46, 7744-65, which are incorporated by reference in their entireties, describe the deuteration of the methylene hydrogens in benzyl amines and efficient pathways to replace aromatic ring hydrogens with deuterium, respectively.
It is to be understood that when a molecular fragment is described as being a substituent or otherwise attached to another moiety, its name may be written as if it were a fragment (e.g. phenyl, phenylene, naphthyl, dibenzofuryl) or as if it were the whole molecule (e.g. benzene, naphthalene, dibenzofuran). As used herein, these different ways of designating a substituent or attached fragment are considered to be equivalent.
In some instance, a pair of adjacent substituents can be optionally joined or fused into a ring. The preferred ring is a five, six, or seven-membered carbocyclic or heterocyclic ring, includes both instances where the portion of the ring formed by the pair of substituents is saturated and where the portion of the ring formed by the pair of substituents is unsaturated. As used herein, “adjacent” means that the two substituents involved can be on the same ring next to each other, or on two neighboring rings having the two closest available substitutable positions, such as 2, 2′ positions in a biphenyl, or 1, 8 position in a naphthalene, as long as they can form a stable fused ring system.
B. The Compounds of the Present Disclosure
In one aspect, the present disclosure provides a compound comprising a metal M and a first ligand LA comprising the structure of
where the compound is capable of functioning as a phosphorescent emitter in an organic light emitting device at room temperature; where, ring A and ring B are each independently a 5-membered or 6-membered carbocyclic or heterocyclic ring; Z1 and Z2 are each independently selected from the group consisting of a direct bond, CR1R2 and CR1R2CR3R4; no more than one of Z1 and Z2 is a direct bond; RA and RB each represent mono to the maximum allowable substitutions, or no substitution; each RA, RB, R1, R2, R3, and R4 is independently a hydrogen or a substituent selected from the group consisting of the general substituents defined herein; at least one of R1, R2, R3, and R4 is a fluorine atom; and any two substituents can be joined or fused to form a ring.
In some embodiments of the compound, each RA, RB, R1, R2, R3, and R4 is independently a hydrogen or a substituent selected from the group consisting of the preferred general substituents defined herein.
In some embodiments of the compound, ring A and ring B are each a 6-membered aromatic ring.
In some embodiments of the compound, the first ligand LA is selected from the group consisting of:
where, ring C is a 5-membered or 6-membered aromatic ring; X1 to X4 are each independently C or N; no more than three of X1 to —X4 is N; the X1 to X4 that is attached to ring C is C; RC represents mono to the maximum allowable substitutions, or no substitution; each RC is a hydrogen or a substituent selected from the group consisting of the general substituents defined herein, and any two substituents can be joined or fused to form a ring; Z is C or N; LA is coordinated to M to form a 5-membered chelate ring; the M coordinated to LA can be coordinated to other ligands; LA can be linked to the ligands to form a tridentate, tetradentate, pentadentate, or hexandentate ligand; and any two substituents can be joined or fused together to form a ring.
In some embodiments of the compound, Z1 is CF2 and Z2 is a direct bond. In some embodiments, Z1 and Z2 are both CF2. In some embodiments, Z1 is CF2, and Z2 is CR1R2, wherein R1 and R2 are each independently a hydrogen or a substituent selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, aryl, heteroaryl, and combinations thereof. In some embodiments, Z2 is a direct bond. In some embodiments, Z1 is CR1R2CR3R4. In some embodiments, Z1 is CF2CF2. In some embodiments, Z1 is CF2CR3R4, where R3 and R4 are each independently a hydrogen or a substituent selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, aryl, heteroaryl, and combinations thereof.
In some embodiments of the compound, ring C is a 6-membered aromatic ring. In some embodiments, two RC substituents are joined together to form a fused 6-membered aromatic ring, which can be further fused.
In some embodiments of the compound, M is selected from the group consisting of Os, Pd, Pt, Ir, Cu, Ag, and Au.
In some embodiments of the compound, the first ligand LA is selected from the group consisting of:
In some embodiments of the compound, the first ligand LA is selected from the group consisting of LA to LA122 whose structures are defined as follows:
where the ligand types 1 through 32 are defined as:
In some embodiments of the compound where the first ligand LA is selected from the group consisting of LA1 to LA122 defined herein, the compound has a formula of M(LA)x(LB)y(LC)z, where LB and LC are each a bidentate ligand; M is Ir or Pt; and wherein x is 1, 2, or 3; y is 0, 1, or 2; z is 0, 1, or 2; and x+y+z is the oxidation state of the metal M.
In some embodiments of the compound having the formula of M(LA)x(LB)y(LC)z, where the first ligand LA is as defined above, the compound has a formula of Pt(LA)(LB); and LA and LB can be same or different. In some embodiments, LA and LB can be connected to form a tetradentate ligand.
In some embodiments of the compound having the formula of M(LA)x(LB)y(LC)z, where the first ligand LA is as defined above, LB and LC can each be independently selected from the group consisting of
where, each Y1 to Y13 are independently selected from the group consisting of carbon and nitrogen; Y′ is selected from the group consisting of B Re, NRe, P Re, O, S, Se, C═O, S═O, SO2, CReRf, SiReRf, and GeReRf; Re and Rf can be fused or joined to form a ring; each Ra, Rb, Rc, and Rd may independently represent from mono substitution to the maximum possible number of substitution, or no substitution; each Ra, Rb, Rc, Rd, Re and Rf is independently a hydrogen or a substituent selected from the group consisting of the general substituents defined herein; and any two adjacent substituents of Ra, Rb, Rc, and Rd can be fused or joined to form a ring or form a multidentate ligand. In some embodiments, LB and LC can each be independently selected from the group consisting of:
In some embodiments of the compound having the formula of M(LA)x(LB)y(LC)z, where the first ligand LA is as defined above, LB can be selected from the group consisting of:
and
LC can be selected from the group consisting of LCj-I, having the structures based on
where j is an integer from 1 to 768, or LCj-II, having the structures based on
where j is an integer from 1 to 768, where for each LCj in LCj-I and LCj-II, R1 and R2 are defined as provided below:
where RD1 to RD192 have the following structures:
In some embodiments of the compound having the formula of M(LA)x(LB)y(LC)z, where the first ligand LA is as defined above, the compound can have a formula selected from the group consisting of Ir(LA)3, Ir(LA)(LB)2, Ir(LA)2(LB), Ir(LA)2(LC), and Ir(LA)(LB)(LC), and LB and LC are as defined above, LA, LB, and LC can be different from each other, any two of them can be the same, or all three can be the same.
In some embodiments of the compound having the formula of Ir(LA)3, Ir(LA)(LB)2, Ir(LA)2(LB), Ir(LA)2(LC), or Ir(LA)(LB)(LC), the compound is the Compound Ax having the formula Ir(LAi)3, the Compound By having the formula Ir(LAi)(LBk)2, or the Compound Cz having the formula Ir(LAi)2(LCj-I) or Ir(LAi)2(LCj-II); where x=i, y=490i+k−263, and z=1260i+j−768; where i is an integer from 1 to 122, and k is an integer from 1 to 263, and j is an integer from 1 to 768; where the structures of LA1 to LA122, LB1 to LB768, LC1-I to LC768-I, and LC1-II to LC768-II are as defined above,
In some embodiments, the compound is selected from the group consisting of:
where, M is Pd or Pt; rings D and E are each independently a 5-membered or 6-membered carbocyclic or heterocyclic ring; M1 and M2 are each independently C or N; Y1 and Y2 are each independently selected from the group consisting of a direct bond, O, and S; at least one of Y and Y2 is a direct bond; L1 and L2 are each independently selected from the group consisting of a direct bond, O, S, CR′R″, SiR′R″, BR′, and NR′; m is 0 or 1; n is 0 or 1; RE can join with RB to form a ring; if RE joins with RB to form a ring, then m+n is 0, 1, or 2; if RE does not join with RB to form a ring, then m+n is 1 or 2; A1 to A3 are each independently C or N; RD and RE each independently represents mono the maximum allowable substitutions, or no substitution; each R′, R″, RD and RE is independently a hydrogen or a substituent selected from the group consisting of the general substituents defined herein; and any two substituents can be joined or fused together to form a ring.
In some embodiments of the compound selected from the group consisting of Formula VII, Formula VIII, Formula IX, and Formula X, ring D and ring E are both 6-membered aromatic rings. In some embodiments, L2 is O or CRR′. In some embodiments, M1 is N and M2 is C. In some embodiments, M1 is C and M2 is N. In some embodiments, L1 is a direct bond. In some embodiments, L1 is NR′. In some embodiments, Y1 and Y2 are both direct bonds. In some embodiments, A1 to A3 are each C. In some embodiments, m+n is 2. In some embodiments, the compound comprises a structure selected from the group consisting of:
RF and RG each independently represents mono the maximum allowable substitutions, or no substitution; each RF and RG is independently a hydrogen or a substituent selected from the group consisting of the general substituents defined herein; and any two substituents can be joined or fused together to form a ring.
Disclosed herein are 9,9-difluoro-9H-fluorene, 9,9-difluoro-10,10-dimethyl-9,10-dihydrophenanthrene, 9,9,10,10-tetrafluoro-9,10-dihydrophenanthrene and their analog fragments and ligands containing one of those fragments that can be used as PHOLED emitter materials. Perfluoroalkyl and difluoroalkyl groups are widely used in the ligands of various complexes used for OLEDs. However, in the ligands of the present disclosure comprise difluoroalkyl groups in dibenzofluorene or dihydrophenanthrene ring systems. This provide possibilities for fine tuning of emission color. Integration of fluorine atoms in the ring system can also increase EQE (external quantum efficiency) of OLED devices. Another advantage of fluorinated rings is that it can probably decrease sublimation temperature of the materials, thus, enabling lower cost OLED fabrication processes. Table 1 below lists DFT calculation results for different Ir complexes with ligands containing CF2 group(s) according to the present disclosure. The DFT data shows that a variety of green, yellow and red emitters can be prepared from the compounds of the present disclosure.
The calculations obtained with the above-identified DFT functional set and basis set are theoretical. Computational composite protocols, such as the Gaussian09 with B3LYP and CEP-31G protocol used herein, rely on the assumption that electronic effects are additive and, therefore, larger basis sets can be used to extrapolate to the complete basis set (CBS) limit. However, when the goal of a study is to understand variations in HOMO, LUMO, S1, T1, bond dissociation energies, etc. over a series of structurally-related compounds, the additive effects are expected to be similar. Accordingly, while absolute errors from using the B3LYP may be significant compared to other computational methods, the relative differences between the HOMO, LUMO, S1, T1, and bond dissociation energy values calculated with B3LYP protocol are expected to reproduce experiment quite well. See, e.g., Hong et al., Chem. Mater. 2016, 28, 5791-98, 5792-93 and Supplemental Information (discussing the reliability of DFT calculations in the context of OLED materials). Moreover, with respect to iridium or platinum complexes that are useful in the OLED art, the data obtained from DFT calculations correlates very well to actual experimental data. See Tavasli et al., J. Mater. Chem. 2012, 22, 6419-29, 6422 (Table 3) (showing DFT calculations closely correlating with actual data for a variety of emissive complexes); Morello, G. R., J. Mol. Model. 2017, 23:174 (studying of a variety of DFT functional sets and basis sets and concluding the combination of B3LYP and CEP-31G is particularly accurate for emissive complexes).
C. The OLEDs and the Devices of the Present Disclosure
In another aspect, the present disclosure also provides an OLED device comprising a first organic layer that contains a compound as disclosed in the above compounds section of the present disclosure.
In some embodiments, the first organic layer comprises a compound comprising a metal M and a first ligand LA comprising the structure of
where the compound is capable of functioning as a phosphorescent emitter in an organic light emitting device at room temperature; where, ring A and ring B are each independently a 5-membered or 6-membered carbocyclic or heterocyclic ring; Z1 and Z2 are each independently selected from the group consisting of a direct bond, CR1R2 and CR1R2CR3R4; no more than one of Z1 and Z2 is a direct bond; RA and RB each represent mono to the maximum allowable substitutions, or no substitution; each RA, RB, R1, R2, R3, and R4 is independently a hydrogen or a substituent selected from the group consisting of the general substituents defined herein; at least one of R1, R2, R3, and R4 is a fluorine atom; and any two substituents can be joined or fused to form a ring.
In some embodiments, the organic layer may be an emissive layer and the compound as described herein may be an emissive dopant or a non-emissive dopant.
In some embodiments, the organic layer may further comprise a host, wherein the host comprises a triphenylene containing benzo-fused thiophene or benzo-fused furan, wherein any substituent in the host is an unfused substituent independently selected from the group consisting of CnH2n+1, OCnH2n+1, OAr1, N(CnH2n+1)2, N(Ar1)(Ar2), CH═CH—CnH2n+1, C≡CCnH2n+1, Ar1, Ar1—Ar2, CnH2n—Ar1, or no substitution, wherein n is from 1 to 10; and wherein Ar1 and Ar2 are independently selected from the group consisting of benzene, biphenyl, naphthalene, triphenylene, carbazole, and heteroaromatic analogs thereof.
In some embodiments, the organic layer may further comprise a host, wherein host comprises at least one chemical group selected from the group consisting of triphenylene, carbazole, dibenzothiphene, dibenzofuran, dibenzoselenophene, azatriphenylene, azacarbazole, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene.
In some embodiments, the host may be selected from the HOST Group consisting of:
and combinations thereof.
In some embodiments, the organic layer may further comprise a host, wherein the host comprises a metal complex.
In some embodiments, the compound as described herein may be a sensitizer; wherein the device may further comprise an acceptor; and wherein the acceptor may be selected from the group consisting of fluorescent emitter, delayed fluorescence emitter, and combination thereof.
In yet another aspect, the OLED of the present disclosure may also comprise an emissive region containing a compound as disclosed in the above compounds section of the present disclosure.
In some embodiments, the emissive region comprises an organic layer comprising a compound comprising a metal M and a first ligand LA comprising the structure of
where the compound is capable of functioning as a phosphorescent emitter in an organic light emitting device at room temperature; where, ring A and ring B are each independently a 5-membered or 6-membered carbocyclic or heterocyclic ring; Z1 and Z2 are each independently selected from the group consisting of a direct bond, CR1R2 and CR1R2CR3R4; no more than one of Z1 and Z2 is a direct bond; RA and RB each represent mono to the maximum allowable substitutions, or no substitution; each RA, RB, R1, R2, R3, and R4 is independently a hydrogen or a substituent selected from the group consisting of the general substituents defined herein; at least one of R1, R2, R3, and R4 is a fluorine atom; and any two substituents can be joined or fused to form a ring.
In yet another aspect, the present disclosure also provides a consumer product comprising an organic light-emitting device (OLED) having an anode; a cathode; and an organic layer disposed between the anode and the cathode, wherein the organic layer may comprise a compound as disclosed in the above compounds section of the present disclosure.
In some embodiments, the consumer product comprises an OLED having an anode; a cathode; and an organic layer disposed between the anode and the cathode, wherein the organic layer comprises a compound comprising a metal M and a first ligand LA comprising the structure of
where the compound is capable of functioning as a phosphorescent emitter in an organic light emitting device at room temperature; where, ring A and ring B are each independently a 5-membered or 6-membered carbocyclic or heterocyclic ring; Z1 and Z2 are each independently selected from the group consisting of a direct bond, CR1R2 and CR1R2CR3R4; no more than one of Z1 and Z2 is a direct bond; RA and RB each represent mono to the maximum allowable substitutions, or no substitution; each RA, RB, R1, R2, R3, and R4 is independently a hydrogen or a substituent selected from the group consisting of the general substituents defined herein; at least one of R1, R2, R3, and R4 is a fluorine atom; and any two substituents can be joined or fused to form a ring.
In some embodiments, the consumer product can be one of a flat panel display, a computer monitor, a medical monitor, a television, a billboard, a light for interior or exterior illumination and/or signaling, a heads-up display, a fully or partially transparent display, a flexible display, a laser printer, a telephone, a cell phone, tablet, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro-display that is less than 2 inches diagonal, a 3-D display, a virtual reality or augmented reality display, a vehicle, a video wall comprising multiple displays tiled together, a theater or stadium screen, a light therapy device, and a sign.
Generally, an OLED comprises at least one organic layer disposed between and electrically connected to an anode and a cathode. When a current is applied, the anode injects holes and the cathode injects electrons into the organic layer(s). The injected holes and electrons each migrate toward the oppositely charged electrode. When an electron and hole localize on the same molecule, an “exciton,” which is a localized electron-hole pair having an excited energy state, is formed. Light is emitted when the exciton relaxes via a photoemissive mechanism. In some cases, the exciton may be localized on an excimer or an exciplex. Non-radiative mechanisms, such as thermal relaxation, may also occur, but are generally considered undesirable.
Several OLED materials and configurations are described in U.S. Pat. Nos. 5,844,363, 6,303,238, and 5,707,745, which are incorporated herein by reference in their entirety.
The initial OLEDs used emissive molecules that emitted light from their singlet states (“fluorescence”) as disclosed, for example, in U.S. Pat. No. 4,769,292, which is incorporated by reference in its entirety. Fluorescent emission generally occurs in a time frame of less than 10 nanoseconds.
More recently, OLEDs having emissive materials that emit light from triplet states (“phosphorescence”) have been demonstrated. Baldo et al., “Highly Efficient Phosphorescent Emission from Organic Electroluminescent Devices,” Nature, vol. 395, 151-154, 1998; (“Baldo-I”) and Baldo et al., “Very high-efficiency green organic light-emitting devices based on electrophosphorescence,” Appl. Phys. Lett., vol. 75, No. 3, 4-6 (1999) (“Baldo-II”), are incorporated by reference in their entireties. Phosphorescence is described in more detail in U.S. Pat. No. 7,279,704 at cols. 5-6, which are incorporated by reference.
More examples for each of these layers are available. For example, a flexible and transparent substrate-anode combination is disclosed in U.S. Pat. No. 5,844,363, which is incorporated by reference in its entirety. An example of a p-doped hole transport layer is m-MTDATA doped with F4-TCNQ at a molar ratio of 50:1, as disclosed in U.S. Patent Application Publication No. 2003/0230980, which is incorporated by reference in its entirety. Examples of emissive and host materials are disclosed in U.S. Pat. No. 6,303,238 to Thompson et al., which is incorporated by reference in its entirety. An example of an n-doped electron transport layer is BPhen doped with Li at a molar ratio of 1:1, as disclosed in U.S. Patent Application Publication No. 2003/0230980, which is incorporated by reference in its entirety. U.S. Pat. Nos. 5,703,436 and 5,707,745, which are incorporated by reference in their entireties, disclose examples of cathodes including compound cathodes having a thin layer of metal such as Mg:Ag with an overlying transparent, electrically-conductive, sputter-deposited ITO layer. The theory and use of blocking layers is described in more detail in U.S. Pat. No. 6,097,147 and U.S. Patent Application Publication No. 2003/0230980, which are incorporated by reference in their entireties. Examples of injection layers are provided in U.S. Patent Application Publication No. 2004/0174116, which is incorporated by reference in its entirety. A description of protective layers may be found in U.S. Patent Application Publication No. 2004/0174116, which is incorporated by reference in its entirety.
The simple layered structure illustrated in
Structures and materials not specifically described may also be used, such as OLEDs comprised of polymeric materials (PLEDs) such as disclosed in U.S. Pat. No. 5,247,190 to Friend et al., which is incorporated by reference in its entirety. By way of further example, OLEDs having a single organic layer may be used. OLEDs may be stacked, for example as described in U.S. Pat. No. 5,707,745 to Forrest et al, which is incorporated by reference in its entirety. The OLED structure may deviate from the simple layered structure illustrated in
Unless otherwise specified, any of the layers of the various embodiments may be deposited by any suitable method. For the organic layers, preferred methods include thermal evaporation, ink-jet, such as described in U.S. Pat. Nos. 6,013,982 and 6,087,196, which are incorporated by reference in their entireties, organic vapor phase deposition (OVPD), such as described in U.S. Pat. No. 6,337,102 to Forrest et al., which is incorporated by reference in its entirety, and deposition by organic vapor jet printing (OVJP), such as described in U.S. Pat. No. 7,431,968, which is incorporated by reference in its entirety. Other suitable deposition methods include spin coating and other solution based processes. Solution based processes are preferably carried out in nitrogen or an inert atmosphere. For the other layers, preferred methods include thermal evaporation. Preferred patterning methods include deposition through a mask, cold welding such as described in U.S. Pat. Nos. 6,294,398 and 6,468,819, which are incorporated by reference in their entireties, and patterning associated with some of the deposition methods such as ink-jet and organic vapor jet printing (OVJP). Other methods may also be used. The materials to be deposited may be modified to make them compatible with a particular deposition method. For example, substituents such as alkyl and aryl groups, branched or unbranched, and preferably containing at least 3 carbons, may be used in small molecules to enhance their ability to undergo solution processing. Substituents having 20 carbons or more may be used, and 3-20 carbons are a preferred range. Materials with asymmetric structures may have better solution processability than those having symmetric structures, because asymmetric materials may have a lower tendency to recrystallize. Dendrimer substituents may be used to enhance the ability of small molecules to undergo solution processing.
Devices fabricated in accordance with embodiments of the present disclosure may further optionally comprise a barrier layer. One purpose of the barrier layer is to protect the electrodes and organic layers from damaging exposure to harmful species in the environment including moisture, vapor and/or gases, etc. The barrier layer may be deposited over, under or next to a substrate, an electrode, or over any other parts of a device including an edge. The barrier layer may comprise a single layer, or multiple layers. The barrier layer may be formed by various known chemical vapor deposition techniques and may include compositions having a single phase as well as compositions having multiple phases. Any suitable material or combination of materials may be used for the barrier layer. The barrier layer may incorporate an inorganic or an organic compound or both. The preferred barrier layer comprises a mixture of a polymeric material and a non-polymeric material as described in U.S. Pat. No. 7,968,146, PCT Pat. Application Nos. PCT/US2007/023098 and PCT/US2009/042829, which are herein incorporated by reference in their entireties. To be considered a “mixture”, the aforesaid polymeric and non-polymeric materials comprising the barrier layer should be deposited under the same reaction conditions and/or at the same time. The weight ratio of polymeric to non-polymeric material may be in the range of 95:5 to 5:95. The polymeric material and the non-polymeric material may be created from the same precursor material. In one example, the mixture of a polymeric material and a non-polymeric material consists essentially of polymeric silicon and inorganic silicon.
Devices fabricated in accordance with embodiments of the present disclosure can be incorporated into a wide variety of electronic component modules (or units) that can be incorporated into a variety of electronic products or intermediate components. Examples of such electronic products or intermediate components include display screens, lighting devices such as discrete light source devices or lighting panels, etc. that can be utilized by the end-user product manufacturers. Such electronic component modules can optionally include the driving electronics and/or power source(s). Devices fabricated in accordance with embodiments of the present disclosure can be incorporated into a wide variety of consumer products that have one or more of the electronic component modules (or units) incorporated therein. A consumer product comprising an OLED that includes the compound of the present disclosure in the organic layer in the OLED is disclosed. Such consumer products would include any kind of products that include one or more light source(s) and/or one or more of some type of visual displays. Some examples of such consumer products include flat panel displays, curved displays, computer monitors, medical monitors, televisions, billboards, lights for interior or exterior illumination and/or signaling, heads-up displays, fully or partially transparent displays, flexible displays, rollable displays, foldable displays, stretchable displays, laser printers, telephones, mobile phones, tablets, phablets, personal digital assistants (PDAs), wearable devices, laptop computers, digital cameras, camcorders, viewfinders, micro-displays (displays that are less than 2 inches diagonal), 3-D displays, virtual reality or augmented reality displays, vehicles, video walls comprising multiple displays tiled together, theater or stadium screen, a light therapy device, and a sign. Various control mechanisms may be used to control devices fabricated in accordance with the present disclosure, including passive matrix and active matrix. Many of the devices are intended for use in a temperature range comfortable to humans, such as 18 degrees C. to 30 degrees C., and more preferably at room temperature (20-25° C.), but could be used outside this temperature range, for example, from −40 degree C. to +80° C.
More details on OLEDs, and the definitions described above, can be found in U.S. Pat. No. 7,279,704, which is incorporated herein by reference in its entirety.
The materials and structures described herein may have applications in devices other than OLEDs. For example, other optoelectronic devices such as organic solar cells and organic photodetectors may employ the materials and structures. More generally, organic devices, such as organic transistors, may employ the materials and structures.
In some embodiments, the OLED has one or more characteristics selected from the group consisting of being flexible, being rollable, being foldable, being stretchable, and being curved. In some embodiments, the OLED is transparent or semi-transparent. In some embodiments, the OLED further comprises a layer comprising carbon nanotubes.
In some embodiments, the OLED further comprises a layer comprising a delayed fluorescent emitter. In some embodiments, the OLED comprises a RGB pixel arrangement or white plus color filter pixel arrangement. In some embodiments, the OLED is a mobile device, a hand held device, or a wearable device. In some embodiments, the OLED is a display panel having less than 10 inch diagonal or 50 square inch area. In some embodiments, the OLED is a display panel having at least 10 inch diagonal or 50 square inch area. In some embodiments, the OLED is a lighting panel.
In some embodiments, the compound can be an emissive dopant. In some embodiments, the compound can produce emissions via phosphorescence, fluorescence, thermally activated delayed fluorescence, i.e., TADF (also referred to as E-type delayed fluorescence; see, e.g., U.S. application Ser. No. 15/700,352, which is hereby incorporated by reference in its entirety), triplet-triplet annihilation, or combinations of these processes. In some embodiments, the emissive dopant can be a racemic mixture, or can be enriched in one enantiomer. In some embodiments, the compound can be homoleptic (each ligand is the same). In some embodiments, the compound can be heteroleptic (at least one ligand is different from others). When there are more than one ligand coordinated to a metal, the ligands can all be the same in some embodiments. In some other embodiments, at least one ligand is different from the other ligands. In some embodiments, every ligand can be different from each other. This is also true in embodiments where a ligand being coordinated to a metal can be linked with other ligands being coordinated to that metal to form a tridentate, tetradentate, pentadentate, or hexadentate ligands. Thus, where the coordinating ligands are being linked together, all of the ligands can be the same in some embodiments, and at least one of the ligands being linked can be different from the other ligand(s) in some other embodiments.
In some embodiments, the compound can be used as a phosphorescent sensitizer in an OLED where one or multiple layers in the OLED contains an acceptor in the form of one or more fluorescent and/or delayed fluorescence emitters. In some embodiments, the compound can be used as one component of an exciplex to be used as a sensitizer. As a phosphorescent sensitizer, the compound must be capable of energy transfer to the acceptor and the acceptor will emit the energy or further transfer energy to a final emitter. The acceptor concentrations can range from 0.001% to 100%. The acceptor could be in either the same layer as the phosphorescent sensitizer or in one or more different layers. In some embodiments, the acceptor is a TADF emitter. In some embodiments, the acceptor is a fluorescent emitter. In some embodiments, the emission can arise from any or all of the sensitizer, acceptor, and final emitter.
According to another aspect, a formulation comprising the compound described herein is also disclosed.
The OLED disclosed herein can be incorporated into one or more of a consumer product, an electronic component module, and a lighting panel. The organic layer can be an emissive layer and the compound can be an emissive dopant in some embodiments, while the compound can be a non-emissive dopant in other embodiments.
In yet another aspect of the present disclosure, a formulation that comprises the novel compound disclosed herein is described. The formulation can include one or more components selected from the group consisting of a solvent, a host, a hole injection material, hole transport material, electron blocking material, hole blocking material, and an electron transport material, disclosed herein.
The present disclosure encompasses any chemical structure comprising the novel compound of the present disclosure, or a monovalent or polyvalent variant thereof. In other words, the inventive compound, or a monovalent or polyvalent variant thereof, can be a part of a larger chemical structure. Such chemical structure can be selected from the group consisting of a monomer, a polymer, a macromolecule, and a supramolecule (also known as supermolecule). As used herein, a “monovalent variant of a compound” refers to a moiety that is identical to the compound except that one hydrogen has been removed and replaced with a bond to the rest of the chemical structure. As used herein, a “polyvalent variant of a compound” refers to a moiety that is identical to the compound except that more than one hydrogen has been removed and replaced with a bond or bonds to the rest of the chemical structure. In the instance of a supramolecule, the inventive compound can also be incorporated into the supramolecule complex without covalent bonds.
D. Combination of the Compounds of the Present Disclosure with Other Materials
The materials described herein as useful for a particular layer in an organic light emitting device may be used in combination with a wide variety of other materials present in the device. For example, emissive dopants disclosed herein may be used in conjunction with a wide variety of hosts, transport layers, blocking layers, injection layers, electrodes and other layers that may be present. The materials described or referred to below are non-limiting examples of materials that may be useful in combination with the compounds disclosed herein, and one of skill in the art can readily consult the literature to identify other materials that may be useful in combination.
a) Conductivity Dopants:
A charge transport layer can be doped with conductivity dopants to substantially alter its density of charge carriers, which will in turn alter its conductivity. The conductivity is increased by generating charge carriers in the matrix material, and depending on the type of dopant, a change in the Fermi level of the semiconductor may also be achieved. Hole-transporting layer can be doped by p-type conductivity dopants and n-type conductivity dopants are used in the electron-transporting layer.
Non-limiting examples of the conductivity dopants that may be used in an OLED in combination with materials disclosed herein are exemplified below together with references that disclose those materials: EP01617493, EP01968131, EP2020694, EP2684932, US20050139810, US20070160905, US20090167167, US2010288362, WO06081780, WO2009003455, WO2009008277, WO2009011327, WO2014009310, US2007252140, US2015060804, US20150123047, and US2012146012.
b) HIL/HTL:
A hole injecting/transporting material to be used in the present disclosure is not particularly limited, and any compound may be used as long as the compound is typically used as a hole injecting/transporting material. Examples of the material include, but are not limited to: a phthalocyanine or porphyrin derivative; an aromatic amine derivative; an indolocarbazole derivative; a polymer containing fluorohydrocarbon; a polymer with conductivity dopants; a conducting polymer, such as PEDOT/PSS; a self-assembly monomer derived from compounds such as phosphonic acid and silane derivatives; a metal oxide derivative, such as MoOx; a p-type semiconducting organic compound, such as 1,4,5,8,9,12-Hexaazatriphenylenehexacarbonitrile; a metal complex, and a cross-linkable compounds.
Examples of aromatic amine derivatives used in HIL or HTL include, but not limit to the following general structures:
Each of Ar1 to Ar9 is selected from the group consisting of aromatic hydrocarbon cyclic compounds such as benzene, biphenyl, triphenyl, triphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, and azulene; the group consisting of aromatic heterocyclic compounds such as dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, pyrrolodipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indoxazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, xanthene, acridine, phenazine, phenothiazine, phenoxazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenodipyridine; and the group consisting of 2 to 10 cyclic structural units which are groups of the same type or different types selected from the aromatic hydrocarbon cyclic group and the aromatic heterocyclic group and are bonded to each other directly or via at least one of oxygen atom, nitrogen atom, sulfur atom, silicon atom, phosphorus atom, boron atom, chain structural unit and the aliphatic cyclic group. Each Ar may be unsubstituted or may be substituted by a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acids, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.
In one aspect, Ar1 to Ar9 is independently selected from the group consisting of:
wherein k is an integer from 1 to 20; X101 to X108 is C (including CH) or N; Z101 is NAr1, O, or S; Ar1 has the same group defined above.
Examples of metal complexes used in HIL or HTL include, but are not limited to the following general formula:
wherein Met is a metal, which can have an atomic weight greater than 40; (Y101-Y102) is a bidentate ligand, Y101 and Y102 are independently selected from C, N, O, P, and S; L101 is an ancillary ligand; k′ is an integer value from 1 to the maximum number of ligands that may be attached to the metal; and k′+k″ is the maximum number of ligands that may be attached to the metal.
In one aspect, (Y101-Y102) is a 2-phenylpyridine derivative. In another aspect, (Y101-Y102) is a carbene ligand. In another aspect, Met is selected from Ir, Pt, Os, and Zn. In a further aspect, the metal complex has a smallest oxidation potential in solution vs. Fc+/Fc couple less than about 0.6 V.
Non-limiting examples of the HIL and HTL materials that may be used in an OLED in combination with materials disclosed herein are exemplified below together with references that disclose those materials: CN102702075, DE102012005215, EP01624500, EP01698613, EP01806334, EP01930964, EP01972613, EP01997799, EP02011790, EP02055700, EP02055701, EP1725079, EP2085382, EP2660300, EP650955, JP07-073529, JP2005112765, JP2007091719, JP2008021687, JP2014-009196, KR20110088898, KR20130077473, TW201139402, U.S. Ser. No. 06/517,957, US20020158242, US20030162053, US20050123751, US20060182993, US20060240279, US20070145888, US20070181874, US20070278938, US20080014464, US20080091025, US20080106190, US20080124572, US20080145707, US20080220265, US20080233434, US20080303417, US2008107919, US20090115320, US20090167161, US2009066235, US2011007385, US20110163302, US2011240968, US2011278551, US2012205642, US2013241401, US20140117329, US2014183517, U.S. Pat. Nos. 5,061,569, 5,639,914, WO05075451, WO07125714, WO08023550, WO08023759, WO2009145016, WO2010061824, WO2011075644, WO2012177006, WO2013018530, WO2013039073, WO2013087142, WO2013118812, WO2013120577, WO2013157367, WO2013175747, WO2014002873, WO2014015935, WO2014015937, WO2014030872, WO2014030921, WO2014034791, WO2014104514, WO2014157018.
c) EBL:
An electron blocking layer (EBL) may be used to reduce the number of electrons and/or excitons that leave the emissive layer. The presence of such a blocking layer in a device may result in substantially higher efficiencies, and/or longer lifetime, as compared to a similar device lacking a blocking layer. Also, a blocking layer may be used to confine emission to a desired region of an OLED. In some embodiments, the EBL material has a higher LUMO (closer to the vacuum level) and/or higher triplet energy than the emitter closest to the EBL interface. In some embodiments, the EBL material has a higher LUMO (closer to the vacuum level) and/or higher triplet energy than one or more of the hosts closest to the EBL interface. In one aspect, the compound used in EBL contains the same molecule or the same functional groups used as one of the hosts described below.
d) Hosts:
The light emitting layer of the organic EL device of the present disclosure preferably contains at least a metal complex as light emitting material, and may contain a host material using the metal complex as a dopant material. Examples of the host material are not particularly limited, and any metal complexes or organic compounds may be used as long as the triplet energy of the host is larger than that of the dopant. Any host material may be used with any dopant so long as the triplet criteria is satisfied.
Examples of metal complexes used as host are preferred to have the following general formula:
wherein Met is a metal; (Y103-Y104) is a bidentate ligand, Y103 and Y104 are independently selected from C, N, O, P, and S; L101 is an another ligand; k′ is an integer value from 1 to the maximum number of ligands that may be attached to the metal; and k′+k″ is the maximum number of ligands that may be attached to the metal.
In one aspect, the metal complexes are:
wherein (O—N) is a bidentate ligand, having metal coordinated to atoms O and N.
In another aspect, Met is selected from Ir and Pt. In a further aspect, (Y103-Y104) is a carbene ligand.
In one aspect, the host compound contains at least one of the following groups selected from the group consisting of aromatic hydrocarbon cyclic compounds such as benzene, biphenyl, triphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, and azulene; the group consisting of aromatic heterocyclic compounds such as dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, pyrrolodipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indoxazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, xanthene, acridine, phenazine, phenothiazine, phenoxazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenodipyridine; and the group consisting of 2 to 10 cyclic structural units which are groups of the same type or different types selected from the aromatic hydrocarbon cyclic group and the aromatic heterocyclic group and are bonded to each other directly or via at least one of oxygen atom, nitrogen atom, sulfur atom, silicon atom, phosphorus atom, boron atom, chain structural unit and the aliphatic cyclic group. Each option within each group may be unsubstituted or may be substituted by a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acids, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.
In one aspect, the host compound contains at least one of the following groups in the molecule:
wherein R101 is selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acids, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof, and when it is aryl or heteroaryl, it has the similar definition as Ar's mentioned above. k is an integer from 0 to 20 or 1 to 20. X101 to X108 are independently selected from C (including CH) or N. Z101 and Z102 are independently selected from NR101, O, or S.
Non-limiting examples of the host materials that may be used in an OLED in combination with materials disclosed herein are exemplified below together with references that disclose those materials: EP2034538, EP2034538A, EP2757608, JP2007254297, KR20100079458, KR20120088644, KR20120129733, KR20130115564, TW201329200, US20030175553, US20050238919, US20060280965, US20090017330, US20090030202, US20090167162, US20090302743, US20090309488, US20100012931, US20100084966, US20100187984, US2010187984, US2012075273, US2012126221, US2013009543, US2013105787, US2013175519, US2014001446, US20140183503, US20140225088, US2014034914, U.S. Pat. No. 7,154,114, WO2001039234, WO2004093207, WO2005014551, WO2005089025, WO2006072002, WO2006114966, WO2007063754, WO2008056746, WO2009003898, WO2009021126, WO2009063833, WO2009066778, WO2009066779, WO2009086028, WO2010056066, WO2010107244, WO2011081423, WO2011081431, WO2011086863, WO2012128298, WO2012133644, WO2012133649, WO2013024872, WO2013035275, WO2013081315, WO2013191404, WO2014142472, US20170263869, US20160163995, U.S. Pat. No. 9,466,803,
e) Additional Emitters:
One or more additional emitter dopants may be used in conjunction with the compound of the present disclosure. Examples of the additional emitter dopants are not particularly limited, and any compounds may be used as long as the compounds are typically used as emitter materials. Examples of suitable emitter materials include, but are not limited to, compounds which can produce emissions via phosphorescence, fluorescence, thermally activated delayed fluorescence, i.e., TADF (also referred to as E-type delayed fluorescence), triplet-triplet annihilation, or combinations of these processes.
Non-limiting examples of the emitter materials that may be used in an OLED in combination with materials disclosed herein are exemplified below together with references that disclose those materials: CN103694277, CN1696137, EB01238981, EP01239526, EP01961743, EP1239526, EP1244155, EP1642951, EP1647554, EP1841834, EP1841834B, EP2062907, EP2730583, JP2012074444, JP2013110263, JP4478555, KR1020090133652, KR20120032054, KR20130043460, TW201332980, U.S. Ser. No. 06/699,599, U.S. Ser. No. 06/916,554, US20010019782, US20020034656, US20030068526, US20030072964, US20030138657, US20050123788, US20050244673, US2005123791, US2005260449, US20060008670, US20060065890, US20060127696, US20060134459, US20060134462, US20060202194, US20060251923, US20070034863, US20070087321, US20070103060, US20070111026, US20070190359, US20070231600, US2007034863, US2007104979, US2007104980, US2007138437, US2007224450, US2007278936, US20080020237, US20080233410, US20080261076, US20080297033, US200805851, US2008161567, US2008210930, US20090039776, US20090108737, US20090115322, US20090179555, US2009085476, US2009104472, US20100090591, US20100148663, US20100244004, US20100295032, US2010102716, US2010105902, US2010244004, US2010270916, US20110057559, US20110108822, US20110204333, US2011215710, US2011227049, US2011285275, US2012292601, US20130146848, US2013033172, US2013165653, US2013181190, US2013334521, US20140246656, US2014103305, U.S. Pat. Nos. 6,303,238, 6,413,656, 6,653,654, 6,670,645, 6,687,266, 6,835,469, 6,921,915, 7,279,704, 7,332,232, 7,378,162, 7,534,505, 7,675,228, 7,728,137, 7,740,957, 7,759,489, 7,951,947, 8,067,099, 8,592,586, 8,871,361, WO06081973, WO06121811, WO07018067, WO07108362, WO07115970, WO07115981, WO8035571, WO2002015645, WO2003040257, WO2005019373, WO2006056418, WO2008054584, WO2008078800, WO2008096609, WO2008101842, WO2009000673, WO2009050281, WO2009100991, WO2010028151, WO2010054731, WO2010086089, WO2010118029, WO2011044988, WO2011051404, WO2011107491, WO2012020327, WO2012163471, WO2013094620, WO2013107487, WO2013174471, WO2014007565, WO2014008982, WO2014023377, WO2014024131, WO2014031977, WO2014038456, WO2014112450.
f) HBL:
A hole blocking layer (HBL) may be used to reduce the number of holes and/or excitons that leave the emissive layer. The presence of such a blocking layer in a device may result in substantially higher efficiencies and/or longer lifetime as compared to a similar device lacking a blocking layer. Also, a blocking layer may be used to confine emission to a desired region of an OLED. In some embodiments, the HBL material has a lower HOMO (further from the vacuum level) and/or higher triplet energy than the emitter closest to the HBL interface. In some embodiments, the HBL material has a lower HOMO (further from the vacuum level) and/or higher triplet energy than one or more of the hosts closest to the HBL interface.
In one aspect, compound used in HBL contains the same molecule or the same functional groups used as host described above.
In another aspect, compound used in HBL contains at least one of the following groups in the molecule:
wherein k is an integer from 1 to 20; L101 is another ligand, k′ is an integer from 1 to 3.
g) ETL:
Electron transport layer (ETL) may include a material capable of transporting electrons. Electron transport layer may be intrinsic (undoped), or doped. Doping may be used to enhance conductivity. Examples of the ETL material are not particularly limited, and any metal complexes or organic compounds may be used as long as they are typically used to transport electrons.
In one aspect, compound used in ETL contains at least one of the following groups in the molecule:
wherein R101 is selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acids, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof, when it is aryl or heteroaryl, it has the similar definition as Ar's mentioned above. Ar1 to Ar3 has the similar definition as Ar's mentioned above. k is an integer from 1 to 20. X101 to X108 is selected from C (including CH) or N.
In another aspect, the metal complexes used in ETL contains, but not limit to the following general formula:
wherein (O—N) or (N—N) is a bidentate ligand, having metal coordinated to atoms O, N or N, N; L101 is another ligand; k′ is an integer value from 1 to the maximum number of ligands that may be attached to the metal.
Non-limiting examples of the ETL materials that may be used in an OLED in combination with materials disclosed herein are exemplified below together with references that disclose those materials: CN103508940, EP01602648, EP01734038, EP01956007, JP2004-022334, JP2005149918, JP2005-268199, KR0117693, KR20130108183, US20040036077, US20070104977, US2007018155, US20090101870, US20090115316, US20090140637, US20090179554, US2009218940, US2010108990, US2011156017, US2011210320, US2012193612, US2012214993, US2014014925, US2014014927, US20140284580, U.S. Pat. Nos. 6,656,612, 8,415,031, WO2003060956, WO2007111263, WO2009148269, WO2010067894, WO2010072300, WO2011074770, WO2011105373, WO2013079217, WO2013145667, WO2013180376, WO2014104499, WO2014104535,
h) Charge Generation Layer (CGL)
In tandem or stacked OLEDs, the CGL plays an essential role in the performance, which is composed of an n-doped layer and a p-doped layer for injection of electrons and holes, respectively. Electrons and holes are supplied from the CGL and electrodes. The consumed electrons and holes in the CGL are refilled by the electrons and holes injected from the cathode and anode, respectively; then, the bipolar currents reach a steady state gradually. Typical CGL materials include n and p conductivity dopants used in the transport layers.
In any above-mentioned compounds used in each layer of the OLED device, the hydrogen atoms can be partially or fully deuterated. Thus, any specifically listed substituent, such as, without limitation, methyl, phenyl, pyridyl, etc. may be undeuterated, partially deuterated, and fully deuterated versions thereof. Similarly, classes of substituents such as, without limitation, alkyl, aryl, cycloalkyl, heteroaryl, etc. also may be undeuterated, partially deuterated, and fully deuterated versions thereof.
It is understood that the various embodiments described herein are byway of example only and are not intended to limit the scope of the invention. For example, many of the materials and structures described herein may be substituted with other materials and structures without deviating from the spirit of the invention. The present invention as claimed may therefore include variations from the particular examples and preferred embodiments described herein, as will be apparent to one of skill in the art. It is understood that various theories as to why the invention works are not intended to be limiting.
Di-p-tolylmethanone (45 g, 214 mmol), silver(I) oxide (69.4 g, 300 mmol), palladium(II) acetate (4.80 g, 21.40 mmol) and potassium carbonate (89 g, 642 mmol) were added to a dry flask. This was then purged with nitrogen (3 times). Trifluoroacetic acid (500 ml) was added and the reaction mixture was heated to 140° C. under nitrogen overnight (about 16 hours). NMR analysis showed starting material was still present. An additional portion of palladium(II) acetate (2 g) was added and the reaction left for another day under nitrogen at 140° C. NMR analysis showed mainly product with some SM. The reaction left for 3 days under nitrogen at 140° C. Once all of the starting material was consumed, the reaction was cooled to RT. The solvent was reduced under vacuum and SiO2 (250 g) and DCM (600 ml) were added. The solvent was evaporated and the crude product was purified by Isolera Biotage (800 g, SiO2, 0-40% DCM:THF 1:1 in heptane). The product containing fractions were combined and evaporated to yield 3,6-dimethyl-9H-fluoren-9-one (43 g, 206 mmol, 96% yield) as an orange solid.
3,6-dimethyl-9H-fluoren-9-one (43 g, 206 mmol), 1-bromopyrrolidine-2,5-dione (38.6 g, 217 mmol), palladium(II) acetate (2.318 g, 10.32 mmol), and potassium persulfate (58.6 g, 217 mmol) were dissolved in 1,2-dichloroethane (21). This was de-oxygenated by bubbling nitrogen through the solution for 30 min. Trifluoromethanesulfonic acid (18 ml, 206 mmol) was then added and the reaction was stirred under nitrogen at 80° C. overnight. Sat. NaHCO3 (aq. 11) was added and the organic layer was separated. The aqueous layer was washed with DCM (2×500 ml) and the combined organic layers were dried (MgSO4). SiO2 (200 g) was added and the solvent evaporated under reduced pressure. The crude was purified by Isolera Biotage (800 g, SiO2, 0-50% DCM in heptane). The product containing fractions were combined and evaporated to yield a yellow solid 1-bromo-3,6-dimethyl-9H-fluoren-9-one (38.8 g, 135 mmol, 65.4% yield). This does contain both SM and the by-product in small quantities and was used without further purification.
1-bromo-3,6-dimethyl-9H-fluoren-9-one (15 g, 52.2 mmol) and ethane-1,2-dithiol (5.26 ml, 62.7 mmol) were dissolved in chloroform (370 ml, Ethanol free). Boron trifluoride diethyl etherate (6.45 ml, 52.2 mmol) was added slowly and the reaction was heated at 80° C. under nitrogen overnight. After all the SM has been consumed, the reaction was cooled to RT and water was added (200 mL). The product was extracted with DCM (3×500 mL) and combined organic layers dried (MgSO4). The solvent was evaporated to yielded a pale yellow solid 1-bromo-3,6-dimethylspiro[fluorene-9,2′-[1,3]dithiolane] which was was used without further purification.
1-Iodopyrrolidine-2,5-dione (52.9 g, 235 mmol) was dissolved in dry DCM (500 ml). The solution was cooled to −78° C. and pyridine hydrofluoride (20.19 ml, 157 mmol) was added slowly. After stirring the solution at −78° C. for 30 min under nitrogen, a solution of 1-bromo-3,6-dimethylspiro[fluorene-9,2′-[1,3]dithiolane] (19 g, 52.3 mmol) in dry DCM (250 mL) was added dropwise. The reaction was stirred for 1 hour at −78° C. and then warmed to RT under nitrogen for 1 hour. After the SM was consumed, water (250 mL) was added and the crude product extracted with DCM (2×250 mL). The combined organic layers were dried (MgSO4), filtered and SiO2 (45 g) was added. The volatiles were removed under vacuum and the product was purified on the Isolera Biotage (330 g, SiO2, 0-10% DCM in heptane). The product containing fractions were combined and evaporated. This yielded 1-bromo-9,9-difluoro-3,6-dimethyl-9H-fluorene (6.4 g, 20.70 mmol, 39.6% yield) as a colourless solid.
1-bromo-9,9-difluoro-3,6-dimethyl-9H-fluorene (6.4 g, 20.70 mmol), 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi(1,3,2-dioxaborolane) (7.89 g, 31.1 mmol) and potassium acetate (6.10 g, 62.1 mmol) were dissolved in Dioxane (130 ml). Nitrogen was bubbled through the solution for 20 min. [1,1′-Bis(diphenylphosphino)ferrocene] dichloropalladium(II), complex with dichloromethane (0.845 g, 1.035 mmol) was added and the reaction heated at 95° C. overnight under nitrogen. After the SM was consumed, the reaction was cooled to RT and DCM (50 ml) was added. The solution was filtered through a pad of celite and the organic layer concentrated under vacuum. This yielded the crude 5-chloro-2-(9,9-difluoro-3,6-dimethyl-9H-fluoren-1-yl)quinoline as a black solid. Which was used without purification.
2-(9,9-Difluoro-3,6-dimethyl-9H-fluoren-1-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (7.37 g, 20.69 mmol), 2,5-dichloroquinoline (4.51 g, 22.76 mmol) and sodium carbonate (5.48 g, 51.7 mmol) were dissolved in Dioxane (100 ml) and water (25 ml). The solution was de-oxygenated by bubbling nitrogen through the solution for 20 min. Tetrakis(triphenylphosphine)palladium(0) (2.391 g, 2.069 mmol) was added and the reaction stirred at 90° C. for overnight under nitrogen. The reaction was cooled and SiO2 (50 g) was added. The solvent was evaporated, and the product purified on an Isolera Biotage (330 g, SiO2, 0-100% DCM in heptane). The product fractions were combined and evaporated to yield a 5-chloro-2-(9,9-difluoro-3,6-dimethyl-9H-fluoren-1-yl)quinoline (5.67 g, 14.47 mmol, 69.9% yield) as a yellow solid.
5-Chloro-2-(9,9-difluoro-3,6-dimethyl-9H-fluoren-1-yl)quinoline (6.24 g, 15.92 mmol), palladium(II) acetate (0.179 g, 0.796 mmol) and XPhos (0.826 g, 1.592 mmol) were placed in a RBF. The flask was purged with nitrogen (vacuum/nitrogen cycle 3×), followed by the addition of neopentylzinc(II) iodide 0.5 M in THF (63.7 ml, 31.8 mmol) under nitrogen. The reaction was heated at 70° C. overnight under nitrogen. The reaction was cooled to RT and SiO2 (25 g) was added. The volatiles were removed under reduced pressure and the product purified on an Isolera Biotage (330 g, SiO2, 0-50% DCM in Heptane). Product containing fractions were combined and evaporated to yield 2-(9,9-difluoro-3,6-dimethyl-9H-fluoren-1-yl)-5-neopentylquinoline (3.45 g, 98.9% purity) as a yellow solid. The product was tritiated with heptane which increased the purity to 99.3%. The solid was dissolving in a minimum of hot benzotrifluoride and cooling overnight to crystallised the product. This yielded 2-(9,9-difluoro-3,6-dimethyl-9H-fluoren-1-yl)-5-neopentylquinoline (3.1 g, 7.25 mmol, 45.5% yield) as an off white solid.
1H-NMR (396 MHz, CHLOROFORM-D): δ 8.51 (d, J=9.1 Hz, 1H), 8.03 (d, J=8.5 Hz, 1H), 7.76-7.76 (m, 1H), 7.67 (dd, J=8.5, 7.3 Hz, 1H), 7.55-7.50 (m, 3H), 7.43 (s, 1H), 7.39-7.37 (m, 1H), 7.15 (d, J=7.3 Hz, 1H), 3.03 (s, 2H), 2.49 (s, 3H), 2.44 (s, 3H), 0.99 (s, 9H) ppm.
19F-NMR (373 MHz, CHLOROFORM-D): δ−110.0 (s, 2F) ppm.
Titanium(IV) chloride 1M in toluene (78 ml, 78 mmol) were added to a dry RBF and cooled to −40° C. dimethylzinc 2M in toluene (78 ml, 157 mmol) was added slowly. This solution was stirred for 30 min at −40° C. under nitrogen, followed by the slow addition of a solution of 1-bromo-3,6-dimethyl-9H-fluoren-9-one (17.3 g, 60.2 mmol) in DCM (300 ml). The reaction was left to warm to RT overnight under nitrogen. After all the SM was consumed, the reaction was cooled to −40° C. and MeOH (40 ml) was added. This was then warmed to RT. DCM (500 mL) and sat. NH4Cl (500 mL) were added and the suspension filtered. The organic layer was separated, and the aqueous layer washed with DCM (500 mL). The combined organic layers were dried (MgSO4) and evaporated to yield a pale brown solid 1-bromo-3,6,9,9-tetramethyl-9H-fluorene (18.2 g, 60.4 mmol, 100% yield). This was used without further purification.
1-bromo-3,6,9,9-tetramethyl-9H-fluorene (18 g, 59.8 mmol) [MST2019-1-078-2], 4,4,4′,4′,5,5,5,5′-octamethyl-2,2′-bi(1,3,2-dioxaborolane) (22.76 g, 90 mmol) and potassium acetate (17.59 g, 179 mmol) were dissolved in Dioxane (350 ml). Nitrogen was bubbled through the solution for 20 min. [1,1′-Bis(diphenylphosphino)ferrocene]dichloropalladium(II), complex with dichloromethane (2.440 g, 2.99 mmol) was added and the reaction heated at 95° C. overnight under nitrogen. Once all the SM had been consumed, DCM (500 mL) was added and the solution filtered through a pad of celite. The organic layer was concentrated to yield a crude 4,4,5,5-tetramethyl-2-(3,6,9,9-tetramethyl-9H-fluoren-1-yl)-1,3,2-dioxaborolane as a black oil. This was used crude in the next reaction.
4,4,5,5-tetramethyl-2-(3,6,9,9-tetramethyl-9H-fluoren-1-yl)-1,3,2-dioxaborolane (20.8 g, 59.7 mmol), 2,5-dichloroquinoline (11.83 g, 59.7 mmol) and sodium carbonate (15.82 g, 149 mmol) were dissolved in de-oxygenated Dioxane (400 ml) and Water (100 ml). Tetrakis(triphenylphosphine)palladium(0) (6.90 g, 5.97 mmol) was added and the reaction stirred at 90° C. for overnight under nitrogen. The solvent was evaporated, and the residue dissolved in DCM (500 mL), sonicated and filtered through dicalite. SiO2 (150 g) was added and the solvent removed. The crude was purification on an Isolera Biotage (350 g, SiO2, 0-50% DCM in heptane). Product containing fractions were combined and evaporated to yield 5-chloro-2-(3,6,9,9-tetramethyl-9H-fluoren-1-yl)quinoline (7.3 g, 19.01 mmol, 46.8% yield) as a colourless solid.
5-chloro-2-(3,6,9,9-tetramethyl-9H-fluoren-1-yl)quinoline (4.4 g, 11.46 mmol), palladium(II) acetate (0.129 g, 0.573 mmol) and XPhos (0.595 g, 1.146 mmol) were placed in a RBF and the flask was purged with nitrogen (vacuum nitrogen cycle×3). Neopentylzinc(II) iodide 0.5 M in THF (45.8 ml, 22.92 mmol) was added and the reaction was heated at 70° C. overnight under nitrogen. After all the starting material was consumed (monitored by LCMS), the reaction was cooled to RT. SiO2 was added (25 g) and the solvent evaporated under reduced pressure. The product was purified on an Isolera Biotage (330 g, SiO2, 0-40% DCM in Heptane). Product containing fractions were combined and evaporated. This yielded 3.4 g of the product. The column was then flashed with DCM-THF (1:1). The wash was combined and evaporated to yield more of the product with other impurities (about 10 g of residue). The combined product batches were combined loaded onto C18 silica and purified by Biotage SP1 (400 g, C18 Biotage, 50-80% THF/ACN 1:1). Product fractions were combined and evaporated to yield 4.39 g of product (99.2% purity by LCMS). The Product was recrystallized from heptane to obtain the desired purity of 5-neopentyl-2-(3,6,9,9-tetramethyl-9H-fluoren-1-yl)quinoline (4.07 g, 9.70 mmol, 61.9% yield).
1H-NMR (MST2019-2-034-10, 396 MHz, CHLOROFORM-D): δ 8.49 (d, J=8.5 Hz, 1H), 8.05 (d, J=8.5 Hz, 1H), 7.68-7.64 (m, 2H), 7.58-7.54 (m, 3H), 7.36 (d, J=7.3 Hz, 1H), 7.32 (d, J=7.3 Hz, 1H), 7.14 (d, J=7.9 Hz, 1H), 3.04 (s, 2H), 2.48 (s, 3H), 2.45 (s, 3H), 1.49 (s, 6H), 1.00 (s, 9H) ppm.
Solution of 2-(9,9-difluoro-3,6-dimethyl-9H-fluoren-1-yl)-5-neopentylquinoline (3.1 g, 7.25 mmol) and iridium chloride hexahydrate (1.21 g, 3.45 mmol) is heated to 130° C. for 72 hours. The mixture is cooled down to room temperature, filtered, and used on the next step as is.
The reaction mixture from the previous step, 3,7-diethylnonane-4,6-dione (1.63 g, 7.67 mmol), potassium carbonate (1.06 g, 7.67 mmol) in THF (60 ml is heated at 50° C. for 14 h. The reaction mixture is diluted with DCM and filter off solids. Filtrate is concentrated, and the residue is purified by column chromatography on silica gel, eluted with heptanes/DCM (2/1 v/v). Pure fractions are evaporated and crystallized from DCM/methanol, providing 1.2 g of the target compound IrLc17(LA47)2.
Solution of 2-(9,9-dimethyl-3,6-dimethyl-9H-fluoren-1-yl)-5-neopentylquinoline (2.9 g, 6.9 mmol) and iridium chloride hexahydrate (1.20 g, 3.40 mmol) is heated to 130° C. for 72 h. The mixture is cooled down to room temperature, filtered, and issued on the next step as is.
The reaction mixture from the previous step, 3,7-diethylnonane-4,6-dione (1.63 g, 7.67 mmol), potassium carbonate (1.06 g, 7.67 mmol) in THF (60 ml is heated at 50° C. for 14 h. The reaction mixture is diluted with DCM and filter off solids. Filtrate is concentrated, and the residue is purified by column chromatography on silica gel, eluted with heptanes/DCM (2/1 v/v). Pure fraction is evaporated and crystallized from DCM/methanol, providing 1.2 g of the Comparison Compound. Comparison of calculated values of IrLC17(LA47)2 and Comparison Compound is presented on the Table and demonstrates that introduction of gem-difluoro group causes 25 nm blue shift of the triplet; it may be beneficial for the color fine-tuning of OLED device. Table 2
This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application No. 62/847,015, filed on May 13, 2019, the entire contents of which are incorporated herein by reference.
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| Number | Date | Country | |
|---|---|---|---|
| 20200361974 A1 | Nov 2020 | US |
| Number | Date | Country | |
|---|---|---|---|
| 62847015 | May 2019 | US |
