MATERIALS FOR ORGANIC ELECTROLUMINESCENT DEVICES

Abstract

The invention relates to compounds of formula (1) which are suitable for use in electronic devices, and to electronic devices, in particular organic electroluminescent devices, containing said compounds. X is, identically or differently in each occurrence, CR or N, or two adjacent X stand for a group of the following formula (2), wherein the dashed bonds mark the bonding of said group in formula (1), with the stipulation that the compound of formula (1) contains one or two groups of formula (2); X.sup.1 is, identically or differently in each occurrence, CR or N; Y is, identically or differently in each occurrence, CR or N; Z.sup.1, Z.sup.2, Z.sup.3 are, identically or differently in each occurrence, O, S, N—Ar or CR.sub.2.

Claims

1. Compound of the formula (1), ##STR00504## where the following applies to the symbols used: X is on each occurrence, identically or differently, CR or N or two adjacent X stand for a group of the following formula (2), ##STR00505## where the dashed bonds denote the linking of this group in the formula (1), with the proviso that the compound of the formula (1) contains one or two groups of the formula (2); X.sup.1 is on each occurrence, identically or differently, CR or N; Y is on each occurrence, identically or differently, CR or N; Z.sup.1, Z.sup.2, Z.sup.3 are on each occurrence, identically or differently, O, S, N—Ar or CR.sub.2; Ar is on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms, which may be substituted by one or more radicals R; R is on each occurrence, identically or differently, H, D, F, Cl, Br, I, N(Ar′).sub.2, N(R.sup.1).sub.2, OAr′, SAr′, CN, NO.sub.2, OR.sup.1, SR.sup.1, COOR.sup.1, C(═O)N(R.sup.1).sub.2, Si(R.sup.1).sub.3, B(OR.sup.1).sub.2, C(═O)R.sup.1, P(═O)(R.sup.1).sub.2, S(═O)R.sup.1, S(═O).sub.2R.sup.1, OSO.sub.2R.sup.1, a straight-chain alkyl group having 1 to 20 C atoms or an alkenyl or alkynyl group having 2 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, where the alkyl, alkenyl or alkynyl group may in each case be substituted by one or more radicals R.sup.1, where one or more non-adjacent CH.sub.2 groups may be replaced by Si(R.sup.1).sub.2, C═O, NR.sup.1, O, S or CONR.sup.1, or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.1; two radicals R may also form an aliphatic, heteroaliphatic, aromatic or heteroaromatic ring system with one another; Ar′ is on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms, which may be substituted by one or more radicals R.sup.1; R.sup.1 is on each occurrence, identically or differently, H, D, F, Cl, Br, I, N(R.sup.2).sub.2, CN, NO.sub.2, OR.sup.2, SR.sup.2, Si(R.sup.2).sub.3, B(OR.sup.2).sub.2, C(═O)R.sup.2, P(═O)(R.sup.2).sub.2, S(═O)R.sup.2, S(═O).sub.2R.sup.2, OSO.sub.2R.sup.2, a straight-chain alkyl group having 1 to 20 C atoms or an alkenyl or alkynyl group having 2 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, where the alkyl, alkenyl or alkynyl group may in each case be substituted by one or more radicals R.sup.2, where one or more non-adjacent CH.sub.2 groups may be replaced by Si(R.sup.2).sub.2, C═O, NR.sup.2, O, S or CONR.sup.2 and where one or more H atoms in the alkyl, alkenyl or alkynyl group may be replaced by D, F, Cl, Br, I or CN, or an aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.2; two or more radicals R.sup.1 may form an aliphatic ring system with one another; R.sup.2 is on each occurrence, identically or differently, H, D, F, CN or an aliphatic, aromatic or heteroaromatic organic radical, in particular a hydrocarbon radical, having 1 to 20 C atoms, in which, in addition, one or more H atoms may be replaced by F.

2. Compound according to claim 1, selected from the compounds of the formulae (3) to (8), ##STR00506## ##STR00507## where the symbols used have the meanings given in claim 1.

3. Compound according to claim 1, wherein the compound contains precisely one group of the formula (2).

4. Compound according to claim 1, wherein the group of the formula (2) stands for a group of the formula (2a), ##STR00508## where the symbols used have the meanings given in claim 1 and the radicals R do not form an aromatic or heteroaromatic ring system with one another.

5. Compound according to claim 1, selected from the structures of the formulae (3a) to (8a), ##STR00509## ##STR00510## where the symbols used have the meanings given in claim 1.

6. Compound according to claim 1, selected from the structures of the formulae (3b) to (8b), ##STR00511## ##STR00512## where the symbols used have the meanings given in claim 1.

7. Compound according to claim 1, wherein Z.sup.1 and Z.sup.2 are selected identically.

8. Compound according to claim 1, wherein at least one of the symbols Z.sup.1, Z.sup.2 and/or Z.sup.3 stands for N—Ar.

9. Compound according to claim 1, selected from the structures of the formulae (3d) to (8d), ##STR00513## ##STR00514## where the symbols used have the meanings given in claim 1.

10. Compound according to claim 1, selected from the structures of the formulae (3e) to (8e), ##STR00515## ##STR00516## where the symbols used have the meanings given in claim 1.

11. Formulation comprising at least one compound according to claim 1 and at least one further compound and/or a solvent.

12. A method comprising including the compound according to claim 1 in an electronic device.

13. Electronic device containing at least one compound according to claim 1.

14. Electronic device according to claim 13, which is an organic electroluminescent device, wherein the compound is employed in an emitting layer as matrix material for phosphorescent emitters or for emitters which exhibit TADF, and/or in an emitting layer as fluorescent emitter and/or in an electron-transport layer and/or in a hole-blocking layer and/or in a hole-transport and/or in an exciton-blocking layer.

15. Electronic device according to claim 14, wherein the compound is employed as matrix material for a phosphorescent emitter in combination with a further matrix material, where the further matrix material is selected from the group consisting of biscarbazoles, bridged carbazoles, triarylamines, dibenzofuran-carbazole derivatives, dibenzofuran-amine derivatives, carbazolamines, indenocarbazoles and indolocarbazoles

Description

EXAMPLES

Synthesis Examples

[0131] The following syntheses are, unless indicated otherwise, carried out under a protective-gas atmosphere in dried solvents. The solvents and reagents can be obtained from ALDRICH or ABCR. The numbers indicated for the starting materials which are not commercially available are the corresponding CAS numbers.

a) 1-(Benzofuran-3-yl)dibenzo[b,d]furan

[0132] ##STR00217##

[0133] Under a protective atmosphere, 20 g (63.2 mmol) of (trifluoromethyl)-sulfonyl)dibenzo[b,d]furan, 11.3 g (69.6 mmol) of benzofuran-3-ylboronic acid, 33.6 g (158.1 mmol) of potassium phosphate, 0.3 g (1.3 mmol) of palladium acetate and 1.2 g (2.5 mmol) of XPhos are heated in a mixture of 100 ml of water and 100 ml of THE under reflux for 17 h. After cooling, the organic phase is separated off, washed three times with 200 ml of water and once with 200 ml of saturated, aqueous sodium chloride solution, dried over magnesium sulfate and evaporated to dryness in a rotary evaporator. The oil is purified by chromatography with heptane. Yield: 15 g (52.8 mmol); 83% of theory.

b)1-(2-Bromobenzofuran-3-yl)dibenzo[b,d]furan

[0134] ##STR00218##

[0135] 15 g (57 mmol) of 1-(benzofuran-3-yl)dibenzo[b,d]furan are dissolved in 150 ml of dichloromethane. 9.4 g (52.7 mmol) of NBS are added in portions to this solution and stirred in the dark for 9 h. Water/ice is then added, the solid is separated off and rinsed with ethanol. The residue is filtered through alumina. Yield: 16.2 g (44 mmol); 84% of theory.

c) ((3-(Dibenzo[b,d]furan-1-yl)benzofuran-2-yl)ethynyl)trimethylsilane

[0136] ##STR00219##

[0137] Under a protective atmosphere, 500 ml of triethylamine are added to 16 g (362 mmol) of 1-(2-bromobenzofuran-3-yl)dibenzo[b,d]furan, 0.3 g (1.3 mmol) of copper iodide, 0.6 g (0.9 mmol) of bis(triphenylphosphine)-palladium(II) chloride and 18.9 ml (133.8 mmol) of trimethylsilylacetylene, and the mixture is boiled under reflux over night. The product is purified by chromatography with heptane. Yield: 13.6 g (35.7 mmol); 80% of theory.

d) 1-(2-Ethynylbenzofuran-3-yl)dibenzo[b,d]furan

[0138] ##STR00220##

[0139] 10 g (26.3 mmol) of ((3-(dibenzo[b,d]furan-1-yl)benzofuran-2-yl)ethynyl)-trimethylsilane, 0.7 g (5.3 mmol) of potassium carbonate are stirred in 100 ml methanol under reflux for 1 h. The solvent is removed in vacuo. 100 ml of dichloromethane and 100 ml of water are added to the mixture. The organic phase is then separated off and subsequently evaporated. Yield: 8.1 g (26.3 mmol); 100% of theory.

e) Naphthobisbenzofuran

[0140] ##STR00221##

[0141] Under a protective atmosphere, 8.1 g (26 mmol) of 1-(2-ethynylbenzo-furan-3-yl)dibenzo[b,d]furan and 690 mg (2.6 mmol) of platinum dichloride are boiled in 500 ml of toluene under reflux overnight. The product is purified by chromatography with toluene. Yield: 3.1 g (10 mmol); 38.7% of theory.

f) 1,8-Bis(2-methylsulfanylphenyl)naphthalene

[0142] ##STR00222##

[0143] 0.71 g (1.7 mmol) of SPhos and 1.68 g (1.7 mmol) of Pd.sub.2(dba).sub.3 are added to a vigorously stirred, degassed suspension of 5 g (17.4 mmol) of 1,8-dibromonaphthalene, 7 g (43.7 mmol) of [2-(methylsulfanylphenyl]boronic acid and 28 g (87 mmol) of caesium carbonate in a mixture of 200 ml of water and 200 ml N,N-dimethylformamide, and the mixture is heated under reflux for 17 h. After cooling, the organic phase is separated off, washed three times with 200 ml of water and once with 200 ml of saturated, aqueous sodium chloride solution, dried over magnesium sulfate and evaporated to dryness in a rotary evaporator. The grey residue is recrystallised from hexane. The deposited crystals are filtered off with suction, washed with a little MeOH and dried in vacuo. Yield: 5.9 g (15.9 mmol); 91% of theory.

g) 1,8-Bis(2-methylsulfinylphenyl)naphthalene

[0144] ##STR00223##

[0145] 30 g (80 mmol) of 1,8-bis[2-methylsulfanylphenyl)naphthalene is initially introduced in 60 ml of glacial acetic acid and cooled to 0° C. 18.2 ml (160 mmol) of a 30% H.sub.2O.sub.2 solution are added dropwise to this solution and stirred overnight. Na.sub.2SO.sub.3 solution is added to the mixture, the phases are separated, and the solvent is removed in vacuo. Yield: 26 g (65 mmol); 80% of theory; purity: 92% according to HPLC.

h) Naphtho[2,1-b:7,8-b′]bis[1]benzothiophene

[0146] ##STR00224##

[0147] A mixture of 54 g (134 mmol) of 1,8-bis(2-methylsulfinylphenyl)naphthalene and 737 ml of trifluoromethanesulfonic acid is stirred at 5° C. for 48 h. 2.41 of water/pyridine 5:1 are subsequently added to the mixture, which is then heated under reflux for 20 min. After cooling to room temperature, 500 ml of water and 1000 ml of dichloromethane are carefully added. The organic phase is washed with 4×50 ml of H.sub.2O, dried over MgSO.sub.4 and the solvent is removed in vacuo. The pure product is obtained by recrystallisation. Yield: 40 g (117 mmol); 80% of theory; purity: 96% according to HPLC.

[0148] The following compounds can be obtained analogously:

TABLE-US-00002 Starting material 1 Product Yield h1 [00225] [00226] 73% h2 [00227] [00228] 77% h3 [00229] [00230] 73% h4 [00231] [00232] 68% h5 [00233] [00234] 80% h6 [00235] [00236] 71% h7 [00237] [00238] 69%

[0149] h1-h4 and h6-h7 are extracted with hot toluene, recrystallised from toluene/n-heptane and finally sublimed in a high vacuum. The purity is 99.9%.

i) Silylation

[0150] ##STR00239##

[0151] 138 ml (245 mmol) of n-buthyllithium (2.5 M in hexane) are added dropwise to a solution, cooled to 15° C., of 82 g (240 mmol) of naphtho-[2,1-b:7,8-b′]bis[1]benzothiophene and 28.3 g (245 mmol) of TMEDA in 1000 ml of THF. The reaction mixture is stirred at room temperature for 3 h, then cooled to 0° C., 27 g (251 mmol) of chlorotrimethylsilane are added dropwise over the course of 30 min. and the mixture is stirred at room temperature for 16 h. The solvent is subsequently removed in vacuo, and the residue is purified by chromatography over silica gel with toluene:dichloromethane 2:2. Yield: 64 g (154 mmol); 65% of theory.

[0152] The following compound can be obtained analogously:

TABLE-US-00003 Starting material Product Yield 1i [00240] [00241] 71%

j) Borylation

[0153] ##STR00242##

[0154] Under a protective gas, 7.8 g (31 mmol) of boron tribromide are added dropwise to a solution of 10.3 g (26 mmol) of compound i in 100 ml of dichloromethane, and the mixture is stirred at room temperature for 10 h. A little water is then slowly added to the mixture, and the precipitated residue is filtered off and washed with heptane. The yield is 9.1 g (24 mmol), corresponding to 95% of theory.

[0155] The following compound can be obtained analogously:

TABLE-US-00004 Starting material 1 Product Yield 1j [00243] [00244] 92%

k) Iodination

[0156] ##STR00245##

[0157] 138 ml (245 mmol) of n-butyllithium (2.5 M in hexane) are added dropwise at −78° C. to a solution, cooled to 15° C., of 82 g (240 mmol) of naphtho-[2,1-b:7,8-b′]bis[1]benzothiophene in 1000 ml of THF. The reaction mixture is stirred at −78° C. for 3 h. 95 g (377 mmol) of iodine dissolved in 400 ml of THE is subsequently slowly added dropwise. The mixture is allowed to come to room temperature, stirred for a further 2 h, 100 ml of saturated Na.sub.2SO.sub.3 solution and 500 ml of ethyl acetate are added to the mixture, the phases are separated, the solvent is removed in vacuo the residue is purified by chromatography over silica gel with toluene:dichloromethane 2:2. Yield: 76 g (164 mmol); 68% of theory.

[0158] The following compounds can be obtained analogously:

TABLE-US-00005 Starting material Product Yield 1k [00246] [00247] 64% 2k [00248] [00249] 60% 3k [00250] [00251] 65% 4k [00252] [00253] 82%

l) Amination

[0159] ##STR00254##

[0160] 55.2 g (140 mmol) of compound k, 18.2 g (142 mmol) of 2-chloroaniline, 68.2 g (710 mmol) of sodium tert-butoxide, 613 mg (3 mmol) of palladium (II) acetate and 3.03 g (5 mmol) of dppf are dissolved in 1.3 1 of toluene and stirred under reflux for 5 h. The reaction mixture is cooled to room temperature, extended with toluene and filtered through Celite. The filtrate is evaporated in vacuo, and the residue is crystallised from toluene/heptane. The product is isolated as a colourless solid. Yield: 44 g (96 mmol); 81% of theory.

[0161] The following compounds can be prepared analogously:

TABLE-US-00006 Starting Starting material 1 material 2 Product Yield 1l [00255] [00256] [00257] 79% 2l [00258] [00259] [00260] 74% 3l [00261] [00262] [00263] 76% 4l [00264] [00265] [00266] 81% 5l [00267] [00268] [00269] 82% 6l [00270] [00271] [00272] 84% 7l [00273] [00274] [00275] 63%

m) Cyclisation

[0162] ##STR00276##

[0163] 41 0.5 g (102 mmol) of compound c, 56 g (409 mmol) of potassium carbonate, 4.5 g (12 mmol) of tricyclohexylphosphine tetrafluoroborate and 1.38 g (6 mmol) of palladium(II) acetate are suspended in 500 ml of dimethylacetamide and stirred under reflux for 6 h. After cooling, 300 ml of water and 400 ml of dichloromethane are added to the reaction mixture. The mixture is stirred for a further 30 min., the organic phase is separated off and filtered through a short Celite bed, and the solvent is then removed in vacuo. The crude product is extracted with hot toluene and recrystallised from toluene. The product is isolated as a beige solid. Yield: 27.5 g (64 mmol); 74% of theory.

[0164] The following compounds can be prepared analogously:

TABLE-US-00007 Starting material Product Yield 1m [00277] [00278] 68% 2m [00279] [00280] 61% 3m [00281] [00282] 60% 4m [00283] [00284] 60% 5m [00285] [00286] 62% 6m [00287] [00288] 71% 7m [00289] [00290] 55%

n) Suzuki Coupling

[0165] ##STR00291##

[0166] 0.85 g (0.74 mmol) of Pd(PPh.sub.3).sub.4 is added to a vigorously stirred, degassed suspension of 43 g (92 mmol) of compound d, 153 g (92 mmol) of 2-nitrophenylboronic acid and 33.2 g (106 mmol) of potassium carbonate in a mixture of 200 ml of water and 200 ml of THE, and the mixture is heated under reflux for 17 h. After cooling, the organic phase is separated off, washed three times with 200 ml of water and once with 200 ml of saturated, aqueous sodium chloride solution, dried over magnesium sulfate and evaporated to dryness in a rotary evaporator. The grey residue is recrystallised from hexane. The deposited crystals are filtered off with suction, washed with a little MeOH and dried in vacuo. Yield: 35.5 g (76.5 mmol); 91% of theory.

[0167] The following compounds can be prepared analogously:

TABLE-US-00008 Starting Starting material 1 material 2 Product Yield  1n [00292] [00293]   [1820664-27-4] [00294] 83%  2n [00295] [00296]   [1199798-20-3] 87%  3n [00297] [00298]   [1642127-06-7] [00299] 81%  4n [00300] [00301]   [5570-19-4] [00302] 73%  5n [00303] [00304]   [5570-19-4] [00305] 75%  6n [00306] [00307]   [5570-19-4] [00308] 79%  7n [00309] [00310]   [5570-19-4] [00311] 70%  8n [00312] [00313]   [5570-19-4] [00314] 65%  9n [00315] [00316]   [5570-19-4] [00317] 70% 10n [00318] [00319]   [850567-97-4] [00320] 87% 11n [00321] [00322]   [850567-97-4] [00323] 79% 6r 12n [00324] [00325]   [850567-97-4] [00326] 71% 5r 13n [00327] [00328]   [850567-97-4] [00329] 65% 1r 14n [00330] [00331]   [850567-97-4] [00332] 72% 2r 15n [00333] [00334]   [850567-97-4] [00335] 76% 7r

o) Carbazole Synthesis

[0168] ##STR00336##

[0169] A mixture of 111 g (240 mmol) of compound n and 290.3 ml (1.7 mol) of triethyl phosphite is heated under reflux for 12 h. The triethyl phosphite remaining is subsequently distilled off (72-76° C./9 mm Hg). Water/MeOH (1:1) is added to the residue, the solid is filtered off and recrystallised. Yield: 75 g (175 mmol); 73% of theory.

[0170] The following compounds can be prepared analogously:

TABLE-US-00009 Starting material Product Yield 1o [00337] [00338] 74% 2o [00339] [00340] 72% 3o [00341] [00342] 81% 4o [00343] [00344] 74% 5o [00345] [00346] 70% 6o [00347] [00348] 71% 7o [00349] [00350] 65% 8o [00351] [00352] 76% 9o [00353] [00354] 77%

p) Nucleophilic Substitution

[0171] ##STR00355##

[0172] 4.2 g of NaH, 60% in mineral oil (106 mmol), are dissolved in 300 ml of dimethylformamide under a protective atmosphere. 54.4 g (106 mmol) of compound f are dissolved in 250 ml of DMF and added dropwise to the reaction mixture. After 1 h at room temperature, a solution of 2-chloro-4,6-diphenyl-1,3,5-triazine (34.5 g, 0.122 mol) in 200 ml THE is added dropwise. The reaction mixture is stirred at room temperature for 12 h and then poured onto ice. After warming to room temperature, the solid which precipitates out is filtered and washed with ethanol and heptane. The residue is extracted with hot toluene, recrystallised from toluene/n-heptane and finally sublimed in a high vacuum. The purity is 99.9%. Yield: 44 g (66 mmol); 63% of theory.

[0173] The following compounds can be prepared analogously:

TABLE-US-00010 Starting Material 1 Starting Material 2 Product Yield  1p [00356] [00357]   [3842-55-5] [00358] 63%  2p [00359] [00360]   [1384480-21-0] [00361] 62%  3p [00362] [00363]   [1373265-66-7] [00364] 59%  4p [00365] [00366]   [1260393-65-4] [00367] 53%  5p [00368] [00369]   2915-16-4 [00370] 60%  6p [00371] [00372]   [1403252-58-3] [00373] 57%  7p [00374] [00375]   [1616499-38-7] [00376] 62%  8p [00377] [00378]   [1373265-66-7] [00379] 64%  9p [00380] [00381]   [30169-34-7] [00382] 65% 10p [00383] [00384]   [1373317-91-9] [00385] 67% 11p [00386] [00387]   [6484-25-9] [00388] 65% 12p [00389] [00390]   [1616499-38-7] [00391] 13p [00392] [00393]   [29874-83-7] [00394] 63% 14p [00395] [00396]   [14003252-55-0] [00397] 67% 15g [00398] [00399]   [1801233-18-0] [00400] 66% 16p [00401] [00402]   [1292317-90-8] [00403] 61% 17p [00404] [00405]   [4787-80-5] [00406] 62% 18p [00407] [00408]   864377-31-1 [00409] 60% 19p [00410] [00411]   [6484-25-9] [00412] 64% 20p [00413] [00414]   [29874-83-7] [00415] 67% 21p [00416] [00417]   [760212-40-6] [00418] 70% 22p [00419] [00420]   [29874-83-7] [00421] 68% 23p [00422] [00423]   864377-31-1 [00424] 66% 24p [00425] [00426]   [29874-83-7] [00427] 64% 25p [00428] [00429]   [29874-83-7] [00430] 74% 26p [00431] [00432]   [29874-83-7] [00433] 61% 27p [00434] [00435]   [29874-83-7] [00436] 60% 28p [00437] [00438]   [3842-55-5] [00439] 72%

q) Buchwald Coupling

[0174] ##STR00440##

[0175] 21.4 g (50 mmol) of compound f and 8.4 g (54 mmol) of bromobenzene are dissolved in 400 ml of toluene under an argon atmosphere. 1.0 g (5 mmol) of tri-tert-butylphosphine are added and stirred under an argon atmosphere. 0.6 g (2 mmol) of Pd(OAc).sub.2 are added and stirred under an argon atmosphere, after which 9.5 g (99 mmol) of sodium tert-butoxide are added. The reaction mixture is stirred under reflux for 24 h. After cooling, the organic phase is separated, washed three times with 200 ml of water, dried over MgSO.sub.4, filtered, and the solvent is removed in vacuo. The residue is purified by column chromatography over silica gel (eluent: DCM/heptane (1:3)), extracted with hot toluene, recrystallised from toluene/n-heptane and finally sublimed in a high vacuum. Yield: 22.7 g (45 mmol); 90% of theory.

[0176] The following compounds are obtained analogously:

TABLE-US-00011 Starting Starting material 1 material 2 Product Yield  1q [00441] [00442]   [19111-87-6] [00443] 70%  2q [00444] [00445]   [1153-85-1] [00446] 73%  3q [00447] [00448]   [212385-73-4] [00449] 75%  4q [00450] [00451] [00452] 76%  5q [00453] [00454] [00455] 78%  6q [00456] [00457] [00458] 70%  7q [00459] [00460] [00461] 73%  8q [00462] [00463] [00464] 75%  9q [00465] [00466] [00467] 70% 10q [00468] [00469] [00470] 77% 11q [00471] [00472] [00473] 51%

r) Bromination

[0177] ##STR00474##

[0178] 111.3 g (190 mmol) of 5,10-dihydro-5-phenyl-10-(4-phenyl-2-quinazolinyl)-carbazolo[3,4-c]carbazole are suspended in 1800 ml of DMF. 34 g (190 mmol) of NBS are added in portions to this suspension and stirred in the dark for 2 h. Water/ice is then added, the solid is separated off and rinsed with ethanol. The isomers are separated by recrystallisation. The yield is 82 g (123 mmol); 65% of theory.

[0179] The following compounds are prepared analogously:

TABLE-US-00012 Starting material Product Yield 1r [00475]   [1980827-30-2] [00476] 54% 2r [00477]   [1980830-96-3] [00478] 52% 3r [00479]   [7259-13-4] [00480] 77% 4r [00481]   [1613254-46-8] [00482] 41% 5r [00483]   [1980833-19-9] [00484] 55% 6r [00485]   [1980830-96-3] [00486] 67% 7r [00487]   [81979232-23-9] [00488] 56%

[0180] Production of OLEDs

[0181] The use of the materials according to the invention in OLEDs is presented in the following examples E1 to E11 (see Table 1).

[0182] Pretreatment for Examples E1-E11: glass plates coated with structured ITO (indium tin oxide) in a thickness of 50 nm are treated, before coating, with an oxygen plasma, followed by an argon plasma. These plasma-treated glass plates form the substrates to which the OLEDs are applied.

[0183] The OLEDs have in principle the following layer structure: substrate/hole-injection layer (HIL)/hole-transport layer (HTL)/electron-blocking layer (EBL)/emission layer (EML)/optional hole-blocking layer (HBL)/electron-transport layer (ETL)/optional electron-injection layer (EIL) and finally a cathode. The cathode is formed by an aluminium layer having a thickness of 100 nm. The precise structure of the OLEDs is shown in Table 1. The materials required for the production of the OLEDs are shown in Table 2. The data for the OLEDs are listed in Table 3.

[0184] All materials are applied by thermal vapour deposition in a vacuum chamber. The emission layer here always consists of at least one matrix material (host material) and an emitting dopant (emitter), which is admixed with the matrix material or matrix materials in a certain proportion by volume by co-evaporation. An expression such as EG1:IC2:TER5 (55%:35%:10%) here means that material EG1 is present in the layer in a proportion by volume of 55%, IC2 is present in the layer in a proportion by volume of 35% and TER5 is present in the layer in a proportion by volume of 10%. Analogously, the electron-transport layer may also consist of a mixture of two materials.

[0185] The OLEDs are characterised by standard methods. For this purpose, the electroluminescence spectra, the current/voltage characteristic lines and the lifetime are determined. The electroluminescence spectra are determined at a luminous density of 1000 cd/m.sup.2 and the CIE 1931 x and y colour coordinates are calculated therefrom. The term U1000 in Table 3 denotes the voltage required for a luminous density of 1000 cd/m.sup.2. The lifetime LT is defined as the time after which the luminous density drops from the initial luminous density to a certain proportion L1 on operation at a constant current density jo. An expression L1=95% in Table 3 means that the lifetime indicated in column LT corresponds to the time after which the luminous density drops to 95% of its initial value.

[0186] Use of the Materials According to the Invention in OLEDs

[0187] Materials EG1 to EG7 according to the invention are employed in Examples E1 to E11 as matrix material in the emission layer of phosphorescent red OLEDs. The particular advantages of these compounds are the comparatively low use voltage, and a long lifetime, which can be significantly extended again in a mixture of a material according to the invention and a co-matrix, in the present case in a mixture of EG1 and IC3.

TABLE-US-00013 TABLE 1 Structure of the OLEDs HIL HTL EBL EML HBL ETL EIL Ex Thickness Thickness Thickness Thickness Thickness Thickness Thickness E1 HATCN SpMA1 SpMA3 EG1:TER5 ST2 ST2:LiQ LiQ 5 nm 125 nm 10 nm (97%:3%) 10 nm (50%:50%) 1 nm 35 nm 30 nm E2 HATCN SpMA1 SpMA3 EG1:IC2:TER5 ST2 ST2:LiQ LiQ 5 nm 125 nm 10 nm (72%:25%:3%) 10 nm (50%:50%) 1 nm 35 nm 30 nm E3 HATCN SpMA1 SpMA3 EG1:IC3:TER5 ST2 ST2:LiQ LiQ 5 nm 125 nm 10 nm (72%:25%:3%) 10 nm (50%:50%) 1 nm 35 nm 30 nm E4 HATCN SpMA1 SpMA3 EG2:IC3:TER5 ST2 ST2:LiQ LiQ 5 nm 125 nm 10 nm (72%:25%:3%) 10 nm (50%:50%) 1 nm 35 nm 30 nm E5 HATCN SpMA1 SpMA3 EG3:IC3:TER5 ST2 ST2:LiQ LiQ 5 nm 125 nm 10 nm (72%:25%:3%) 10 nm (50%:50%) 1 nm 35 nm 30 nm E6 HATCN SpMA1 SpMA3 EG4:IC3:TER5 ST2 ST2:LiQ LiQ 5 nm 125 nm 10 nm (72%:25%:3%) 10 nm (50%:50%) 1 nm 35 nm 30 nm E7 HATCN SpMA1 SpMA3 EG5:IC3:TER5 ST2 ST2:LiQ LiQ 5 nm 125 nm 10 nm (72%:25%:3%) 10 nm (50%:50%) 1 nm 35 nm 30 nm E8 HATCN SpMA1 SpMA3 EG6:TER5 ST2 ST2:LiQ LiQ 5 nm 125 nm 10 nm (97%:3%) 10 nm (50%:50%) 1 nm 35 nm 30 nm E9 HATCN SpMA1 SpMA3 EG6:IC2:TER5 ST2 ST2:LiQ LiQ 5 nm 125 nm 10 nm (72%:25%:3%) 10 nm (50%:50%) 1 nm 35 nm 30 nm E20 HATCN SpMA1 SpMA3 EG7:TER5 ST2 ST2:LiQ LiQ 5 nm 125 nm 10 nm (97%:3%) 10 nm (50%:50%) 1 nm 35 nm 30 nm E11 HATCN SpMA1 SpMA3 EG7:IC2:TER5 ST2 ST2:LiQ LiQ 5 nm 125 nm 10 nm (72%:25%:3%) 10 nm (50%:50%) 1 nm 35 nm 30 nm

TABLE-US-00014 TABLE 2 Structural formulae of the materials for the OLEDs [00489] HATCN [00490] SpMA1 [00491] SpMA3 [00492] TER5 [00493] IC2 [00494] LiQ [00495] ST2 [00496] IC3 [00497] EG1 [00498] EG2 [00499] EG3 [00500] EG4 [00501] EG5 [00502] EG6 [00503] EG7

TABLE-US-00015 TABLE 3 Data of the OLEDs U1000 CIE x/y at j.sub.0 EQE 1000 L1 LT Ex. (V) 1000 cd/m.sup.2 (mA/cm.sup.2) % (%) (h) E1 3.3 0.67/0.33 20 19 95 520 E2 3.5 0.67/0.34 20 20 95 410 E3 3.4 0.67/0.33 20 21.2 95 375 E4 3.3 0.67/0.34 20 21.1 95 400 E5 3.3 0.67/0.33 20 20.5 95 337 E6 3.4 0.67/0.33 20 20.3 95 391 E7 3.3 0.67/0.33 20 20.1 95 430 E8 3.3 0.67/0.33 20 24.0 95 220 E9 3.4 0.67/0.33 20 25.6 95 230 E10 3.1 0.67/0.33 20 22.7 95 300 E11 3.2 0.67/0.33 20 26.3 95 490

[0188] Comparable results are obtained with the other compounds described in the synthesis examples in a device having an analogous structure to Examples E1 and E2.