Patent Application
20220251077
The present invention relates generally to a compound, and, more specifically, to an organic electroluminescence (herein after referred to as organic EL) device using the compound.
An organic electroluminescence (organic EL) devices, i.e., organic light-emitting diodes (OLEDs) that make use of organic compounds, are becoming increasingly desirable than before. One of the organic compounds has the following formula:
An organic EL device is a light-emitting diode (LED) in which the light emitting layer is a film made from organic compounds, which emits light in response to an electric current. The light emitting layer containing the organic compound is sandwiched between two electrodes. The organic EL device is applied to flat panel displays due to its high illumination, low weight, ultra-thin profile, self-illumination without back light, low power consumption, wide viewing angle, high contrast, simple fabrication methods and rapid response time.
However, there is still a need for improvement in the case of use of those organic materials in an organic EL device of some prior art displays, for example, in relation to the lifetime, current efficiency or driving voltage of the organic EL device.
According to the reasons described above, an object of the present invention is to resolve the problems of prior arts and to offer a novel compound.
Another object of the invention is to provide an organic EL device using the compound. The organic EL device of the present invention may operate under reduced voltage, or may exhibit higher current efficiency or longer lifetime.
The present invention discloses an organic compound of formula (1):
wherein Y is selected from the group consisting of O, S, Se, NR1, CR2R3 and SiR4R5; X is CR6 or N, and at least one X is N, and two adjacent X can form a five-membered ring, a six-membered ring or a combination thereof; L represents a single bond, a substituted or unsubstituted divalent arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted divalent heteroarylene group having 6 to 30 ring carbon atoms; A represents a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 30 ring carbon atoms; R1 to R6 are independently selected from the group consisting of a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 6 to 30 carbon atoms and a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms.
The present invention further discloses an organic EL device. The organic EL device may comprise an anode, a cathode and one or more organic layers formed between the anode and the cathode. At least one of the organic layers comprises the organic compound of formula (1).
Generally, an external voltage is applied across the organic EL device, electrons and holes are injected from the cathode and the anode, respectively. Electrons will be injected from a cathode into a LUMO (lowest unoccupied molecular orbital) and holes will be injected from an anode into a HOMO (highest occupied molecular orbital). Subsequently, the electrons recombine with holes in the light emitting layer to form excitons and then emit light. When luminescent molecules absorb energy to achieve an excited state, the exciton may either be in a singlet state or a triplet state, depending on how the spins of the electrons and holes have been combined.
The terms “halogen” and “halide” are used interchangeably and refer to fluorine, chlorine, bromine, and iodine.
The term “alkyl” or “alkyl group” refers to and includes both straight and branched chain alkyl radicals. Preferred alkyl groups are those containing from 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms. Suitable alkyl groups include 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 is optionally substituted.
The term “aryl” or “aryl group” refers to and includes both single-ring aromatic hydrocarbonyl groups and polycyclic aromatic ring systems. The polycyclic rings may have two, three, four 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 hydrocarbonyl group, e.g., the other rings can be cycloalkyls, cycloalkenyls, aryl, heterocycles, and/or heteroaryls. Preferred aryl groups are those containing 6 to 30 carbon atoms, preferably 6 to 20 carbon atoms, more preferably 6 to 12 carbon atoms. Especially preferred is an aryl group having 6 carbons, 10 carbons or 12 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, and naphthalene. Additionally, the aryl group is optionally substituted.
The terms “aralkyl”, “aralkyl group” or “arylalkyl” are used interchangeably and refer to an alkyl group that is substituted with an aryl group. Preferred aralkyl groups are those containing 6 to 30 carbon atoms. Additionally, the aralkyl group is optionally substituted.
The term “heteroaryl” or “heteroaryl group” 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 3 to 30 carbon atoms, preferably 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms. Suitable heteroaryl groups include pyrimidine, triazine, quinazoline, benzoquinazoline, phenylquinazoline, dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, pyrrolodipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indoxazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, 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 is optionally substituted.
The terms “R1” to “R18” may independently be H (hydrogen) or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, aralkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, and combinations thereof. R1 to R18 may preferably and independently be hydrogen or a substituent selected from the group consisting of hydrogen, alkyl, aryl, aralkyl, heteroaryl, and combinations thereof.
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 fragment can be replaced by a nitrogen atom, for example, and without any limitation, azatriphenylene encompasses both dibenzo[fh]quinoxaline and dibenzo[fh]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.
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, 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, and combinations thereof.
In some instances, the preferred general substituents are selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, alkoxy, aryloxy, amino, silyl, aryl, heteroaryl, sulfanyl, and combinations thereof.
In yet other instances, the more 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 R1 represents mono-substitution, then one R1 must be other than H (i.e., a substitution). Similarly, when R1 represents di-substitution, then two of R1 must be other than H. Similarly, when R1 represents 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, two adjacent alkyls can form a five-membered ring, a six-membered ring or a combination thereof. Moreover, 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.
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 a first embodiment of the present invention, an organic compound which can be used as the host material of the light emitting layer in the organic EL device is disclosed. The organic compound may be represented by the following formula (1):
Y is selected from the group consisting of O, S, Se, NR1, CR2R3 and SiR4R5; X is CR6 or N, and at least one X is N, and two adjacent X can form a five-membered or six-membered ring; L represents a single bond, a substituted or unsubstituted divalent arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted divalent heteroarylene group having 6 to 30 ring carbon atoms; A represents a substituted or unsubstituted divalent arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted divalent heteroarylene group having 5 to 30 ring carbon atoms; R1 to R6 are independently selected from the group consisting of H, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 6 to 30 carbon atoms and a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms.
Preferably, at least one of the following may be true:
only one X is N;
at least eleven X are not N; and
at least eleven X are CH.
The alkyl group, aralkyl group, aryl group, or heteroaryl group may be substituted by a halogen, an alkyl group, an aryl group, or a heteroaryl group.
A may be selected from the group consisting of pyrimidinyl, triazinyl, fluorenyl, quinazolinyl, benzoquinazolinyl, phenylquinazolinyl,
and combinations thereof.
The organic compound may be represented by the following formula (2):
Y is selected from the group consisting of O, S, Se, NR1, CR2R3 and SiR4R5;
L represents a single bond, a substituted or unsubstituted divalent arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted divalent heteroarylene group having 6 to 30 ring carbon atoms.
X7 is N or CR7;
wherein X8 is N or CR8;
wherein X9 is N or CR9;
wherein X10 is N or CR10;
wherein X11 is N or CR11;
wherein X12 is N or CR12;
wherein X13 is N or CR13;
wherein X14 is N or CR14;
wherein X15 is N or CR15;
wherein X16 is N or CR16;
wherein X17 is N or CR17;
wherein X18 is N or CR18; and
wherein at least one of X7 to X18 is N.
Y may be selected from the group consisting of O, S, Se, NR1, CR2R3 and SiR4R5. R1 to R5 may be independently selected from the group consisting of methyl, ethyl, phenyl, naphthyl, hexylbenzenyl, pyrimidinyl, quinolinyl, and combinations thereof. R7 to R18 may be independently selected from the group consisting of H, an aryl group having 6 carbon atoms, an alkyl group having 1, 2 or 3 carbon atoms, and a heteroaryl group having 3, 4 or 5 carbon atoms.
Adjacent two of X7 to X18 may form a five-membered ring, a six-membered ring or a combination thereof.
In formula (2), A may represent an aryl group having 6 to 30 ring carbon atoms, or a heteroaryl group including one to two heteroatoms of N and having 5 to 30 ring carbon atoms.
At least one of the following may be true:
only one of X7 to X18 is N;
at least eleven of X7 to X18 are not N;
at least eleven of X7 to X18 are CH;
at least one of X7 to X9 may be N;
at least one of X7 and X8 may be N;
one of X7 to X9 may be N; and
one of X7 and X8 may be N.
Preferably, only one of X7 to X9 is N. Alternatively, only one of X7 and X8 is N.
More preferably, X8 may be N.
In case of at least one of X7 to X9 is N, X11 to X14 may preferably be not N, the heteroaryl group represented by A may preferably include two heteroatoms of N. The two heteroatoms of N are more preferably located in a single aromatic ring. The organic compounds comprising such A may each serve as an emitting host material of an organic EL device. The organic EL device may be operated under reduced driving voltage of about 5.6 V to about 6.0 V. See compounds 261, 155, 135, 55, 45, 35, 126, 206, 257, 196, 173, 90, 235, 66, 187, 25 of Table 1.
R1 to R6 may be independently selected from the group consisting of H, an alkyl group having 1 to 6 carbon atoms,
and combinations thereof.
R7 to R18 may be independently selected from the group consisting of H, an aryl group having 6 carbon atoms, an alkyl group having 1, 2 or 3 carbon atoms, and a heteroaryl group having 3, 4 or 5 carbon atoms. Adjacent two of X7 to X18 can form a five-membered ring, a six-membered ring or a combination thereof.
Referring to
As the host 340C of the first organic EL device 510 of
In a third embodiment of the present invention, a second organic EL device using the organic compound of formula (1) is disclosed.
Referring to
Referring to
In a fourth embodiment of the present invention, a third organic EL device using the organic compound of formula (1) is disclosed.
Referring to
Referring to
In the organic compound, the alkyl group, aralkyl group, aryl group, or heteroaryl group may be substituted by a halogen, an alkyl group, an aryl group, or a heteroaryl group.
In the organic compound of formula (1) or formula (2), A may be selected from phenyl, pyridinyl, triazinyl, naphthyl, fluorenyl, quinazolinyl, benzoquinazolinyl, phenylquinazolinyl,
and combinations thereof. Preferably, A may be selected from
and combinations thereof.
Preferably, the organic compound may be selected from the group consisting of the following compounds:
An organic electroluminescence device comprising an anode, a cathode and one or more organic layers formed between the anode and the cathode, wherein at least one of the organic layers comprises the organic compound of formula (1).
The organic layers may comprise an emissive layer having a host, and wherein the organic compound is comprised as the host.
The organic layers may comprise an electron transfer layer, and wherein the organic compound of formula (1) is comprised as the electron transfer layer.
The organic compound of formula (1) may be a hole blocking material.
The organic electroluminescence device may be a lighting panel.
The organic electroluminescence device may be a backlight panel.
Referring to
The emissive layer 340E may comprise a 15% dopant D1 and the organic compound of formula (1) 340C doped with the dopant D1. The dopant D1 may be a red guest material for tuning the wavelength at which the emissive layer 340E emits light, so that the color of emitted light may be green. The organic compound of formula (1) may be a host 340C of the emissive layer 340E.
To those organic EL devices of
The I-V-B (at 1000 nits) test reports of those organic EL devices of
According to Table 1, in the first organic EL device 510, the organic compound of formula (1) comprised as a host 340 of
A method of producing the first organic EL device 510 of
Before vapor deposition of the organic layers, cleaned ITO substrates may be further treated by UV and ozone. All pre-treatment processes for ITO substrate are under clean room (class 100), so that an anode 310 may be formed.
One or more organic layers 320, 330, 340 (
Referring to
N,N-Bis(naphthalene-1-yl)-N,N-bis(phenyl)-benzidine (NPB) may be applied to form a hole transporting layer(HTL) 330 having a thickness of about 110 nm.
Referring to
Referring to
On the emissive layer 340 having a thickness of about 30 nm, a compound HB1 may be a hole blocking material (HBM) to form a hole blocking layer (HBL) 350 having a thickness of about 10 nm. 2-(naphthalen-1-yl)-9-(4-(1-(4-(10-(naphthalene-2-yl)anthracen-9-yl)-phenyl)-1H-benzo[d]imidazol-2-yl)phenyl)-1,10-phenanthroline(ET1) may be applied as an electron transporting material to co-deposit with 8-hydroxyquinolato-lithium(LiQ) at a ratio of 1:1, thereby forming an electron transporting layer 360 of the organic EL device 510 or 400. The electron transporting layer (ETL) 360 may have a thickness of about 35 nm. Table 2 shows the layer thickness and materials of the organic EL device 510 (
The organic compounds HAT-CN, NPB, D1, H1, HB1 and ET1 for producing the organic EL device 400 or 510 in this invention may have the formulas as follows:
Referring to
In a third embodiment of the present invention, a second organic EL device using the organic compound of formula (1) is disclosed. The method of producing the second organic EL device 520 of
Table 3 shows the layer thickness and materials of the organic EL device 520 (
To those organic EL devices of
In a fourth embodiment of the present invention, a third organic EL device using the organic compound of formula (1) is disclosed. The method of producing the third organic EL device 530 of
Table 4 shows the layer thickness and materials of the organic EL device 530 (
To those organic EL devices of
The I-V-B(at 1000 nits) test reports of those organic EL devices of
According to Table 5, in the second organic EL device 520, the organic compound of formula (1) comprised as a hole blocking layer 350C of
According to Table 5, in the third organic EL device 530, the organic compound of formula (1) comprised as an electron transfer layer 360C of
Referring to
Referring to
Detailed preparation of the organic compounds of the present invention will be clarified by exemplary embodiments below, but the present invention is not limited thereto. EXAMPLES 1 to 34 show the preparation of the organic compounds of the present invention.
A mixture of 10 g (31.8 mmol) of 5-bromobenzo[4,5]thieno[3,2-h]-isoquinoline, 9.7 g (38.2 mmol) of bis(pinacolato)diboron, 0.74 g (0.6 mmol) of Pd(Ph3)4, 6.24 g (63.6 mmol) of potassium acetate, and 150 ml of 1,4-dioxane was degassed and placed under nitrogen, and then heated to reflux for 12 hrs. After the reaction finished, the mixture was allowed to cool to room temperature. Subsequently, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography, yielding 8.8 g of 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzo-[4,5]thieno[3,2-h]isoquinoline as white solid (76.5%). 1H NMR (CDCl3, 400 MHz): chemical shift (ppm) 8.88 (s, 1H), 8.41 (d, 1H), 8.19 (d, 1H), 7.98 (d, 1H), 7.51-7.47 (m, 3H), 7.41 (d, 1H), 1.26 (s, 12H).
A mixture of 8.8 g (24.4 mmol) of 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzo[4,5]thieno[3,2-h]isoquinoline, 5.4 g (26.8 mmol) of 1-bromo-2-nitrobenzene, 0.56 g (0.5 mmol) of Pd(Ph3)4, 24.4 ml of 2 M Na2CO3, 30 ml of EtOH and 90 ml of toluene was degassed and placed under nitrogen, and then heated to reflux for 12 hrs. After the reaction finished, the mixture was allowed to cool to room temperature. Subsequently, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography, yielding 6 g of 5-(2-nitrophenyl)benzo[4,5]thieno-[3,2-h]isoquinoline as yellow solid (69.1%). 1H NMR (CDCl3, 400 MHz): chemical shift (ppm) 8.89 (s, 1H), 8.43 (m, 2H), 8.03-7.99 (m, 3H), 7.88 (m,1H), 7.79 (s, 1H), 7.66 (m, 1H), 7.53-7.48 (m, 3H).
A mixture of 6 g (16.8 mmol) of 5-(2-nitrophenyl)benzo[4,5]thieno-[3,2-h]isoquinoline, 17.7 g (67.3 mmol) of triphenylphosphine, and 60 ml of o-dichlorobenzene was degassed and placed under nitrogen, and then heated to reflux for 12 hrs. After the reaction finished, the mixture was allowed to cool to room temperature. Subsequently, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography, yielding 3.4 g of 14H-benzo[4,5]thieno[3,2-a]pyrido[3,4-c]carbazole as white solid (62.3%). 1H NMR (CDCl3, 400 MHz): chemical shift (ppm) 10.1 (s, 1H), 8.91 (s, 1H), 8.45 (m, 2H), 8.13 (d, 1H), 7.98 (d,1H), 7.64 (m, 1H), 7.53-7.48 (m, 4H), 7.26 (m, 1H).
A mixture of 3.4 g (10.5 mmol) of 14H-benzo[4,5]thieno[3,2-a]pyrido-[3,4-c]carbazole, 3.6 g (12.6 mmol) of 2-bromo-4-phenylquinazoline, 0.2 g (0.2 mmol) of Pd2(dba)3, 0.21 g (1 mmol) of P(t-Bu)3, 2 g (21 mmol) of NaOtBu, 40 ml of toluene was degassed and placed under nitrogen, and then heated to reflux for 12 hrs. After the reaction finished, the mixture was allowed to cool to room temperature. Subsequently, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography, yielding 3.8 g of 14-(4-phenylquinazolin-2-yl)-14H-benzo[4,5]thieno[3,2-a]-pyrido[3,4-c]carbazole as yellow solid (68.6%). 1H NMR (CDCl3, 400 MHz): chemical shift (ppm) 8.92 (s, 1H), 8.53 (d, 1H), 8.45 (m, 2H), 8.18 (d, 1H), 8.03-7.95 (m, 4H), 7.81 (m, 3H), 7.53-7.48 (m, 5H), 7.40 (m, 1H), 7.34 (m, 1H), 7.24 (m, 1H).
A mixture of 10 g (33.5 mmol) of 5-bromobenzofuro[3,2-h]quinoline, 10.2 g (40.2 mmol) of bis(pinacolato)diboron, 0.78 g (0.67 mmol) of Pd(Ph3)4, 6.58 g (67.1 mmol) of potassium acetate, and 150 ml of 1,4-dioxane was degassed and placed under nitrogen, and then heated to reflux for 12 hrs. After the reaction finished, the mixture was allowed to cool to room temperature. Subsequently, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography, yielding 8.2 g of 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzofuro-[3,2-h]quinoline as white solid (70.8%). 1H NMR (CDCl3, 400 MHz): chemical shift (ppm) 8.85 (d, 1H), 8.39 (d, 1H), 7.89 (d, 1H), 7.64-7.59 (d, 3H), 7.37-7.33 (m, 2H), 1.26 (s, 12H).
A mixture of 8.2 g (23.8 mmol) of 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzofuro [3,2-h]quinoline, 5.3 g (26.1 mmol) of 1-bromo-2-nitrobenzene, 0.55 g (0.48 mmol) of Pd(Ph3)4, 23.8 ml of 2M Na2CO3, 30 ml of EtOH and 90 ml of toluene was degassed and placed under nitrogen, and then heated to reflux for 12 hrs. After the reaction finished, the mixture was allowed to cool to room temperature. Subsequently, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography, yielding 5.8 g of 5-(2-nitrophenyl)benzofuro[3,2-h]quinoline as yellow solid (71.8%). 1H NMR (CDCl3, 400 MHz): chemical shift (ppm) 8.84 (d, 1H), 8.39 (d, 1H), 8.05-8.01 (m, 2H), 7.91-7.88 (m, 2H), 7-68-7.64 (m, 3H), 7.57 (m, 1H), 7.37-7.33 (m, 2H).
A mixture of 5.8 g (17 mmol) of 5-(2-nitrophenyl)benzofuro[3,2-h]-quinoline, 17.9 g (68.1 mmol) of triphenylphosphine, and 60 ml of o-dichlorobenzene was degassed and placed under nitrogen, and then heated to reflux for 12 hrs. After the reaction finished, the mixture was allowed to cool to room temperature. Subsequently, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography, yielding 3.3 g of 14H-benzofuro[3,2-a]pyrido[2,3-c]carbazole as white solid (62.8%). 1H NMR (CDCl3, 400 MHz): chemical shift (ppm) 10.1 (s, 1H), 8.84 (d, 1H), 8.39 (d, 1H), 8.14 (d, 1H), 7.91 (d, 1H), 7.65-7.59 (m, 3H), 7.48(m, 1H), 7.36-7.30 (m, 3H).
A mixture of 3.3 g (10.7 mmol) of 14H-benzofuro[3,2-a]pyrido[2,3-c]-carbazole, 3.66 g (11.8 mmol) of 2-bromo-4,6-diphenylpyrimidine, 0.2 g (0.2 mmol) of Pd2(dba)3, 0.22 g (1 mmol) of P(t-Bu)3, 2.1 g (21.4 mmol) of NaOtBu, 40 ml of toluene was degassed and placed under nitrogen, and then heated to reflux for 12 hrs. After the reaction finished, the mixture was allowed to cool to room temperature. Subsequently, the solvent was removed under reduced pressure, and the crude product was purified by column chromatography, yielding 3.9 g of 14-(4,6-diphenylpyrimidin-2-yl)-14H-benzofuro[3,2-a]pyrido[2,3-c]carbazole as white solid (67.7%). 1H NMR (CDCl3, 400 MHz): chemical shift (ppm) 8.84 (d, 1H), 8.62 (s, 1H), 8.54 (d, 1H), 8.39 (d, 1H), 7.93-7.90 (m, 2H), 7.78 (d, 4H), 7.67 (d, 1H), 7.56-7.43 (m, 8H), 7.32-7.27 (m, 3H).
We have used the same synthesis methods to get a series of intermediates and the following compounds are synthesized analogously.
It is understood that the various embodiments described herein are by way 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 solely by the appended claims.
