HETEROCYCLIC COMPOUND FOR USE IN ELECTRONIC DEVICES

Abstract

The present invention relates to heterocyclic compounds, especially for use in electronic devices. The invention further relates to a process for preparing the compounds of the invention and to electronic devices comprising these.

Claims

1. Compound comprising at least one structure of the formula (I): ##STR00578## where the symbols used are as follows: X is the same or different at each instance and is N or CR; R.sup.a is the same or different at each instance and is H, D, OH, F, Cl, Br, I, CN, NO.sub.2, N(Ar.sup.a).sub.2, N(R).sub.2, C(═O) Ar.sup.a, C(═O)R.sup.2, P(═O)(Ar.sup.a).sub.2, P(Ar.sup.a).sub.2, B(Ar.sup.a).sub.2, B(OR).sub.2, Si(Ar.sup.a).sub.3, Si(R).sub.3, a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 carbon atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 40 carbon atoms or an alkenyl or alkynyl group having 2 to 40 carbon atoms, each of which may be substituted by one or more R radicals, where one or more nonadjacent CH.sub.2 groups may be replaced by —RC═CR—, —C≡C—, Si(R).sub.2, Ge(R).sub.2, Sn(R).sub.2, C═O, C═S, —O—, —Se—, —S—, C═Se, —C(═O)O—, —C(═O)NR—, C═NR, NR, P(═O)(R), SO or SO.sub.2 and where one or more hydrogen atoms may be replaced by D, F, Cl, Br, I, CN or NO.sub.2, or an aromatic or heteroaromatic ring system which has 5 to 60 aromatic ring atoms, each of which may be substituted by one or more R radicals, or an aryloxy or heteroaryloxy group which has 5 to 60 aromatic ring atoms and may be substituted by one or more R radicals, or an aralkyl or heteroaralkyl group which has 5 to 60 aromatic ring atoms and may be substituted by one or more R radicals, or a combination of these systems; at the same time, two or more R.sup.a radicals may form a ring system with one another or with an R radical; Ar.sup.a is the same or different at each instance and is an aromatic or heteroaromatic ring system which has 5 to 30 aromatic ring atoms and may be substituted by one or more nonaromatic R radicals; at the same time, it is possible for two Ar.sup.a radicals bonded to the same silicon atom, nitrogen atom, phosphorus atom or boron atom also to be joined together via a bridge by a single bond or a bridge selected from B(R), C(R).sub.2, Si(R).sub.2, C═O, C═NR, C═C(R).sub.2, O, S, Se, S═O, SO.sub.2, N(R), P(R) and P(═O)R; R is the same or different at each instance and is H, D, OH, F, Cl, Br, I, CN, NO.sub.2, N(Ar).sub.2, N(R.sup.1).sub.2, C(═O)Ar, C(═O)R.sup.1, P(═O)(Ar).sub.2, P(Ar).sub.2, B(Ar).sub.2, B(OR.sup.1).sub.2, Si(Ar).sub.3, Si(R.sup.1).sub.3, a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 carbon atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 40 carbon atoms or an alkenyl or alkynyl group having 2 to 40 carbon atoms, each of which may be substituted by one or more R.sup.2 radicals, where one or more nonadjacent CH.sub.2 groups may be replaced by —R.sup.1C═CR.sup.1—, —C≡C—, Si(R.sup.1).sub.2, Ge(R.sup.1).sub.2, Sn(R.sup.1).sub.2, C═O, C═S, C═Se, —C(═O)O—, —C(═O)NR.sup.1—, C═NR.sup.1, NR.sup.1, P(═O)(R.sup.1), —O—, —S—, —Se—, SO or SO.sub.2 and where one or more hydrogen atoms may be replaced by D, F, Cl, Br, I, CN or NO.sub.2, or an aromatic or heteroaromatic ring system which has 5 to 60 aromatic ring atoms, each of which may be substituted by one or more R.sup.1 radicals, or an aryloxy or heteroaryloxy group which has 5 to 60 aromatic ring atoms and may be substituted by one or more R.sup.1 radicals, or an aralkyl or heteroaralkyl group which has 5 to 60 aromatic ring atoms and may be substituted by one or more R.sup.1 radicals, or a combination of these systems; at the same time, two or more R.sup.1 radicals may form a ring system with one another; Ar is the same or different at each instance and is an aromatic or heteroaromatic ring system which has 5 to 30 aromatic ring atoms and may be substituted by one or more nonaromatic R.sup.1 radicals; at the same time, it is possible for two Ar radicals bonded to the same silicon atom, nitrogen atom, phosphorus atom or boron atom also to be joined together via a bridge by a single bond or a bridge selected from B(R.sup.1), C(R.sup.1).sub.2, Si(R.sup.1).sub.2, C═O, C═NR.sup.1, C═C(R.sup.1).sub.2, O, S, Se, S═O, SO.sub.2, N(R.sup.1), P(R.sup.1) and P(═O)R.sup.1; R.sup.1 is the same or different at each instance and is H, D, OH, F, Cl, Br, I, CN, NO.sub.2, N(Ar.sup.1).sub.2, N(R.sup.2).sub.2, C(═O)Ar.sup.1, C(═O)R.sup.2, P(═O)(Ar.sup.1).sub.2, P(Ar.sup.1).sub.2, B(Ar.sup.1).sub.2, B(OR.sup.2).sub.2, Si(Ar.sup.1).sub.3, Si(R.sup.2).sub.3, a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 carbon atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 40 carbon atoms or an alkenyl or alkynyl group having 2 to 40 carbon atoms, each of which may be substituted by one or more R.sup.2 radicals, where one or more nonadjacent CH.sub.2 groups may be replaced by —R.sup.2C═CR.sup.2—, —C≡C—, Si(R.sup.2).sub.2, Ge(R.sup.2).sub.2, Sn(R.sup.2).sub.2, C═O, C═S, C═Se, C═NR.sup.2, —C(═O)O—, —C(═O)NR.sup.2—, NR.sup.2, P(═O)(R.sup.2), —O—, —S—, —Se—, SO or SO.sub.2 and where one or more hydrogen atoms may be replaced by D, F, Cl, Br, I, CN or NO.sub.2, or an aromatic or heteroaromatic ring system which has 5 to 40 aromatic ring atoms and may be substituted in each case by one or more R.sup.2 radicals, or an aryloxy or heteroaryloxy group which has 5 to 40 aromatic ring atoms and may be substituted by one or more R.sup.2 radicals, or an aralkyl or heteroaralkyl group which has 5 to 40 aromatic ring atoms and may be substituted by one or more R.sup.2 radicals, or a combination of these systems; at the same time, two or more R.sup.1 radicals may form a ring system with one another; Ar.sup.1 is the same or different at each instance and is an aromatic or heteroaromatic ring system which has 5 to 30 aromatic ring atoms and may be substituted by one or more nonaromatic R.sup.2 radicals; at the same time, it is possible for two Ar.sup.1 radicals bonded to the same silicon atom, nitrogen atom, phosphorus atom or boron atom also to be joined together via a bridge by a single bond or a bridge selected from B(R.sup.2), C(R.sup.2).sub.2, Si(R.sup.2).sub.2, C═O, C═NR.sup.2, C═C(R.sup.2).sub.2, O, S, Se, S═O, SO.sub.2, N(R.sup.2), P(R.sup.2) and P(═O)R.sup.2; R.sup.2 is the same or different at each instance and is H, D, F, Cl, Br, I, CN, B(OR.sup.3).sub.2, NO.sub.2, C(═O)R.sup.3, CR.sup.3═C(R.sup.3).sub.2, C(═O)OR.sup.3, C(═O)N(R.sup.3).sub.2, Si(R.sup.3).sub.3, P(R.sup.3).sub.2, B(R.sup.3).sub.2, N(R.sup.3).sub.2, NO.sub.2, P(═O)(R.sup.3).sub.2, OSO.sub.2R.sup.3, OR.sup.3, S(═O)R.sup.3, S(═O).sub.2R.sup.3, a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 carbon atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 40 carbon atoms, each of which may be substituted by one or more R.sup.3 radicals, where one or more nonadjacent CH.sub.2 groups may be replaced by —R.sup.3C═CR.sup.3—, —C≡C—, Si(R.sup.3).sub.2, Ge(R.sup.3).sub.2, Sn(R.sup.3).sub.2, C═O, C═S, C═NR.sup.3, —C(═O)O—, —C(═O)NR.sup.3—, NR.sup.3, P(═O)(R.sup.3), —O—, —S—, —Se—, SO or SO.sub.2 and where one or more hydrogen atoms may be replaced by D, F, Cl, Br, I, CN or NO.sub.2, or an aromatic or heteroaromatic ring system which has 5 to 40 aromatic ring atoms and may be substituted in each case by one or more R.sup.3 radicals, or an aryloxy or heteroaryloxy group which has 5 to 40 aromatic ring atoms and may be substituted by one or more R.sup.3 radicals, or a combination of these systems; at the same time, two or more R.sup.2 substituents may also form a ring system with one another; R.sup.3 is the same or different at each instance and is selected from the group consisting of H, D, F, CN, an aliphatic hydrocarbyl radical having 1 to 20 carbon atoms, and an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms in which one or more hydrogen atoms may be replaced by D, F, Cl, Br, I or CN and which may be substituted by one or more alkyl groups each having 1 to 4 carbon atoms; at the same time, it is possible for two or more R.sup.3 substituents to form a ring system with one another.

2. Compound according to claim 1, comprising at least one structure of the formula (IIa), (IIb), (IIc) or (IId) ##STR00579## where the symbols R and X have the definition given in claim 1, p is 0 or 1 and Y is B(R), C(R).sub.2, Si(R).sub.2, C═O, C═NR, C═C(R).sub.2, O, S, Se, S═O, SO.sub.2, N(R), P(R) and P(═O)R.

3. Compound according to claim 1, comprising at least one structure of the formula (IIIa), (IIIb), (IIIc) or (IIId) ##STR00580## where the symbol R has the definition given in claim 1, the symbols Y and p have the definition given in claim 4, l is 1, 2, 3, 4 or 5 and m is 0, 1, 2, 3 or 4.

4. Compound according to claim 1, wherein the compound comprises a hole transport group, where preferably one of the R.sup.a groups or one of the R groups comprises a hole transport group.

5. Compound according to claim 9, wherein the hole transport group comprises a group selected from the formulae (H-1) to (H-3) ##STR00581## where the dotted bond marks the position of attachment and Ar.sup.2, Ar.sup.3, Ar.sup.4 are each independently an aromatic ring system having 6 to 40 carbon atoms or a heteroaromatic ring system having 3 to 40 carbon atoms, each of which may be substituted by one or more R.sup.1 radicals; P is 0 or 1, and W.sup.1 is C(R.sup.1).sub.2, Si(R.sup.1).sub.2, C═O, N—Ar.sup.1, BR.sup.1, PR.sup.1, POR.sup.1, SO, SO.sub.2, Se, O or S, where the symbols Ar.sup.1 and R.sup.1 have the definition given in claim 1, where the presence of an N—N bond is ruled out, and so, in the case that Y═NR or NAr, the index p=1.

6. Compound according to claim 1, wherein the compound comprises an electron transport group, where one of the R.sup.a groups or one of the R groups comprises is an electron transport group.

7. Compound according to claim 6, wherein one of the R.sup.a groups or one of the R groups comprises a hole transport group that can be represented by the formula (QL)
Q-L.sup.1-   Formula (QL) in which L.sup.1 represents a bond or an aromatic or heteroaromatic ring system which has 5 to 40 aromatic ring atoms and may be substituted by one or more R.sup.1 radicals, and Q is an electron transport group, where R.sup.1 has the definition given in claim 1.

8. Compound according to claim 1, wherein at least one R.sup.a or R group in the formulae (I), (IIa), (IIb), (IIc), (IId), (IIIa), (IIIb), (IIIc) or (IIId) is a group that can be represented by the formula L.sup.1-Z in which L.sup.1 represents a bond or an aromatic or heteroaromatic ring system which has 5 to 40 aromatic ring atoms and may be substituted by one or more R.sup.1 radicals, Z is R.sup.1, Ar or a group of the formula Z.sup.a or Z.sup.b, in which the symbols Ar and R.sup.1 have the definition given in claim 1 and Z.sup.a or Z.sup.b are ##STR00582## in which W is the same or different at each instance and is an aromatic or heteroaromatic ring system which has 5 to 30 aromatic ring atoms and may be substituted by one or more R.sup.1 radicals, a nitrogen atom, a boron atom, a phosphorus atom or a phosphine oxide group, the dotted bond marks the position of attachment and the symbols Ar and R.sup.1 have the definition given in claim 1.

9. Compound according to claim 8, comprising at least one structure of the formula (IVa), (IVb), (IVc), (IVd), (IVe), (IVf), (IVg), (IVh), (IVi), (IVj), (IVk), (IVl), (IVm), (IVn), (IVo), (IVp), (IVq), (IVr), (IVs), (IVt), (IVu), (IVv), (IVw), (IVx) or (IVy) ##STR00583## ##STR00584## ##STR00585## ##STR00586## ##STR00587## where the symbol R.sup.1 has the definition given in claim 1, the symbols L.sup.1 and Z have the definition given in claim 8, l is 1, 2, 3, 4 or 5, m is 0, 1, 2, 3 or 4 and n is 0, 1, 2 or 3.

10. Compound according to claim 8, comprising at least one structure of the formula (Va), (Vb), (Vc), (Vd), (Ve), (Vf), (Vg) or (Vh) ##STR00588## ##STR00589## where the symbol R.sup.1 has the definition given in claim 1, the symbols L.sup.1 and Z have the definition given in claim 8, m is 0, 1, 2, 3 or 4, and n is 0, 1, 2 or 3.

11. Compound according to claim 8, comprising at least one structure of the formula (VIa), (VIb), (VIc), (VId), (VIe), (VIf), (VIg), (VIh), (VIi), (VIj), (VIk), (VIl), VIm), (VIn), (VIo), (VIp), (VIq), (VIr), (VIs) or (VIt) ##STR00590## ##STR00591## ##STR00592## ##STR00593## ##STR00594## where the symbol R.sup.1 has the definition given in claim 1, the symbols L.sup.1 and Z have the definition given in claim 8, l is 1, 2, 3, 4 or 5 m is 0, 1, 2, 3 or 4, and n is 0, 1, 2 or 3.

12. Oligomer, polymer or dendrimer containing one or more compounds according to claim 1, wherein, rather than a hydrogen atom or a substituent, there are one or more bonds of the compounds to the polymer, oligomer or dendrimer.

13. Composition comprising at least one compound according to claim 1 or an oligomer, polymer or dendrimer comprising a compound of claim 1 as a substituent, and at least one further compound selected from the group consisting of fluorescent emitters, phosphorescent emitters, polypodal emitters, emitters that exhibit TADF (thermally activated delayed fluorescence), host materials, electron transport materials, electron injection materials, hole conductor materials, hole injection materials, electron blocker materials and hole blocker materials.

14. Formulation comprising at least one compound according to claim 1 or an oligomer, polymer or dendrimer comprising a compound of claim 1 as a substituent, and at least one solvent.

15. Use of a compound according to claim 1, of an oligomer, polymer or dendrimer comprising a compound of claim 1 as a substituent in an electronic device as host material, hole transport material or electron transport material.

16. Process for preparing a compound according to claim 1 or an oligomer, polymer or dendrimer comprising a compound of claim 1 as a substituent, wherein in a coupling reaction, a compound comprising at least one nitrogen-containing heterocyclic group is joined to a compound comprising at least one aromatic or heteroaromatic group.

17. Electronic device comprising at least one compound according to claim 1, an oligomer, polymer or dendrimer comprising a compound of claim 1 as a substituent, wherein the electronic device is selected from the group consisting of organic electroluminescent devices, organic integrated circuits, organic field-effect transistors, organic thin-film transistors, organic light-emitting transistors, organic solar cells, organic optical detectors, organic photoreceptors, organic field-quench devices, light-emitting electrochemical cells and organic laser diodes.

18. Compound according to claim 1, wherein X is CR.

19. Compound according to claim 2, wherein Y is B(R), C(R).sub.2, Si(R).sub.2, O, S, Se, S═O, SO.sub.2, N(R), P(R) and P(═O)R.

20. Compound according to claim 3, wherein 1 is 0, 1 or 2 and m is 0, 1 or 2.

21. Compound according to claim 5, wherein W.sup.1 is C(R.sup.1).sub.2, N—Ar.sup.1, O or S.

Description

EXAMPLES

[0262] The syntheses which follow, unless stated otherwise, are conducted under a protective gas atmosphere in dried solvents. The reactants can be sourced from ALDRICH. The numbers for the reactants known from the literature, some of which are stated in square brackets, are the corresponding CAS numbers.

SYNTHESIS EXAMPLES

[0263] ##STR00393##

Synthesis Examples

a) 1-Bromo-4b,9-diazaindeno[1,2-a]inden-10-one

[0264] ##STR00394##

[0265] In a 2 l flask, 89.0 g (754 mmol; 1.50 eq) of benzimidazole [CAS 51-17-2], 102 g (502 mmol; 1.00 eq) of 2-bromo-6-fluorobenzaldehyde [CAS 360575-28-6] and 108 g (778 mmol; 1.55 eq) of potassium carbonate [CAS 584-08-7] are suspended in 1500 ml of DMSO [CAS 67-68-5]. The reaction mixture is stirred with introduction of air at 105° C. for 18 hours. After cooling to room temperature, the reaction is poured onto 2.5 l of ice-water. The precipitated solids are filtered off and washed with ethyl acetate [CAS 141-78-6]. The product 43.3 g (144.7 mmol, 29% of theory) is obtained as an orange solid.

[0266] In an analogous manner, it is possible to obtain the following compounds:

TABLE-US-00005 No. Reactant 1 Reactant 2 Product Yield 1a [00395] [00396] [00397] 17% 2a [00398] [00399] [00400] 21% 3a [00401] [00402] [00403] 19% 4a [00404] [00405] [00406] 15% 5a [00407] [00408] [00409] 25% 6a [00410] [00411] [00412] 16%

b) 10-(4′-Chlorobiphenyl-2-yl)-10H-4b,9-diazaindeno[1,2-a]inden-10-ol

[0267] ##STR00413##

[0268] In a 1 l flask, under protective gas, 20.9 g (78.2 mmol; 1.07 eq) of 2-bromo-4′-chlorobiphenyl [CAS 179526-95-5] are dissolved in 50 ml of dry THF [CAS 109-99-9] and cooled to −78° C. Then 30.7 ml (2.5 mol/l; 76.7 mmol; 1.05 eq) of n-butyllithium [CAS 109-72-8] are added dropwise and the mixture is stirred for a further 2 hours. A suspension of 16.1 g (73.0 mmol, 1.00 eq) of 4b,9-diazaindeno[1,2-a]inden-10-one [CAS 138479-49-9] in 370 ml of dry THF [CAS 109-99-9] is added dropwise to this mixture. The resulting mixture is warmed gradually to room temperature and stirred for a further 18 hours.

[0269] The reaction is quenched by addition of 300 ml of water and the resulting phases are separated. After the aqueous phase has been extracted with ethyl acetate (3×150 ml) [CAS 141-78-6], the combined organic phases are washed with water (2×150 ml). Removing the solvent under reduced pressure gives the crude product, which is finally dissolved in dichloromethane [CAS 75-09-2] and precipitated by addition of heptane. After filtration, 25.3 g (61.8 mmol; 85%) of the product can be obtained as a brownish filter residue.

[0270] In an analogous manner, it is possible to obtain the following compounds:

TABLE-US-00006 No. Reactant 1 Reactant 2 Product Yield 1b [00414] [00415] [00416] 82% 2b [00417] [00418] [00419] 62% 3b [00420] [00421] [00422] 79% 4b [00423] [00424] [00425] 88% 5b [00426] [00427] [00428] 55% 6b [00429] [00430] [00431] 73% 7b [00432] [00433] [00434] 78% 8b [00435] [00436] [00437] 48%

c) 2-Chlorospiro[fluorene-9,11-indolo[1,2-a]benzimidazole]

[0271] ##STR00438##

[0272] In a 500 ml flask, 24.9 g (60.9 mmol; 1.00 eq) of 10-(4′-chlorobiphenyl-2-yl)-10H-4b,9-diazaindeno[1,2-a]inden-10-ol and 116 g (609 mmol; 10.0 eq) of toluenesulfonic acid monohydrate [CAS 6192-52-5] are suspended in 290 ml of toluene [CAS 108-88-3], and the mixture is stirred at 115° C. for 72 hours. On completion of conversion, the mixture is cooled down to room temperature and the reaction solution is concentrated. The crude product is taken up in ethyl acetate (500 ml) [CAS 141-78-6] and washed with water (2×250 ml). After filtration through silica gel and precipitating with heptane, 19.1 g (80%, 48.8 mmol) of the product are obtained in the form of a beige solid.

[0273] In an analogous manner, it is possible to obtain the following compounds:

TABLE-US-00007 No. Reactant 1 Product Yield 1c [00439] [00440] 80% 2c [00441] [00442] 76% 3c [00443] [00444] 66% 4c [00445] [00446] 73% 5c [00447] [00448] 81% 6c [00449] [00450] 69% 7c [00451] [00452] 77% 8c [00453] [00454] 81% 9c [00455] [00456] 58%

d) 2-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)spiro[fluorene-9,11′-indolo[1,2-a]benzimidazole]

[0274] ##STR00457##

[0275] In a 1 l flask, under protective gas, 18.6 g (47.5 mmol; 1.00 eq) of 2-chlorospiro[fluorene-9,11′-indolo[1,2-a]benzimidazole] and 14.5 g (57 mmol, 1.20 eq) of bis(pinacolato)diborane [CAS 73183-34-3] are dissolved in 450 ml of dry dioxane [CAS 123-91-1] and the mixture is degassed for 30 minutes. Subsequently, 10.2 g (105 mmol, 2.20 eq.) of potassium acetate [CAS 127-08-2] and 1.76 g (2.38 mmol, 5 mol %) of trans-dichlorobis(tricyclohexylphosphine)palladium(II) complex [CAS 29934-17-6] are added, and the mixture is heated to 90° C. overnight. After the reaction has ended, the mixture is diluted with 300 ml of toluene [CAS 108-88-3] and extracted with water. The solvent is removed on a rotary evaporator and the solids obtained are dried. 17.9 g of the product (37.1 mmol, 78% of theory) are converted without further purification.

[0276] In an analogous manner, it is possible to obtain the following compounds:

TABLE-US-00008 No. Reactant 1 Product Yield 1d [00458] [00459] 83% 2d [00460] [00461] 73% 3d [00462] [00463] 72%

e) 10,10-dimethyl-1,8-diazatetracyclo[7.7.0.0.SUP.2,7..0.SUP.11,16.]hexadeca-2,4,6,8,11(16),12,14-heptaene

[0277] ##STR00464##

[0278] Under an inertized atmosphere, 147 g (774 mmol, 4.00 eq.) of titanium(IV) chloride [CAS 7550-45-0] and dichloromethane [CAS 75-09-2] are initially charged at −40° C. Then 387 ml (2 mol/l, 774 mmol, 4.00 eq) of dimethylzinc solution [CAS 544-97-8] are added at such a rate that a temperature of −35° C. is not exceeded. Subsequently, 42.6 g (193.6 mmol, 1.00 eq) of 4b,9-diazaindeno[1,2-a]inden-10-one are added. The solution obtained is warmed gradually to room temperature and quenched by addition of ethanol and subsequently water. The phases are separated and the organic phase is concentrated to the solids. The crude product is recrystallized repeatedly from a mixture of heptane [CAS 142-82-5] and ethyl acetate [CAS 141-78-6]. 5.03 g (21.3 mmol, 11% of theory) of product are obtained.

f) 5-bromo-10,10-dimethyl-1,8-diazatetracyclo[7.7.0.0.SUP.2,7.0.SUP.11,16.]hexadeca-2,4,6,8,11(16),12,14-heptaene

[0279] ##STR00465##

[0280] Under protective gas, 4.83 g (20.6 mmol, 1.00 eq.) of 3-[3′-(4,6-diphenyl-1,3,5-triazin-2-yl)-[1,1′-biphenyl]-3-yl]-9-(triphenylen-2-yl)-9H-carbazole are suspended in 30 ml of dry DMF [CAS 68-12-2] and cooled to 0° C. Then 4.03 g (22.7 mmol, 1.1 eq.) of NBS [CAS 128-08-5] are added, and the reaction mixture is stirred for 16 h, in the course of which it is warmed to room temperature. The reaction is quenched by addition of 150 ml of water and stirred for 30 min. After filtration and drying, 5.48 g (17.5 mmol; 85% of theory) of product can be obtained.

g) N-(9,9-Dimethylfluoren-4-yl)-N-(4-phenylphenyl)spiro[fluorene-9,11′-indolo[1,2-a]benzimidazole]-2-amine

[0281] ##STR00466##

[0282] An initial charge of 15.2 g (38.9 mmol; 1.00 eq.) of 2-chlorospiro[fluorene-9,11′-indolo[1,2-a]benzimidazole], 14.5 g (39.3 mmol; 1.01 eq.) of biphenyl-4-yl-(9,9-dimethyl-9H-fluoren-4-yl)amine [CAS 1421789-16-3] and 4.96 g (42.7 mmol; 1.10 eq.) of sodium tert-pentoxide [CAS 14593-46-5] in 200 ml of toluene [CAS 108-88-3] is inertized in argon stream for 30 minutes. Then 479 mg (1.17 mmol; 3 mol %) of dicyclohexyl-(2′,6′-dimethoxybiphenyl-2-yl)phosphine (SPhos) [CAS 657408-07-6], 262 mg (1.17 mmol; 3 mol %) of palladium acetate [CAS 3375-31-3] are added and the mixture is heated to reflux for 18 hours. After completion of conversion and cooling to room temperature, 500 ml of water are added to the reaction. After separation of the phases and extraction of the aqueous phase with toluene [CAS 108-88-3], the combined organic phases are concentrated and heptane is added. The precipitated solids are isolated. Purification by means of Soxhlet extraction, recrystallization and vacuum sublimation gives the desired product (6.63 g; 9.26 mmol; 24% of theory).

[0283] In an analogous manner, it is possible to obtain the following compounds:

TABLE-US-00009 No. Reactant 1 Product Yield  1g [00467] [00468] [00469] 30%  2g [00470] [00471] [00472] 33%  3g [00473] [00474] [00475] 28%  4g [00476] [00477] [00478] 44%  5g [00479] [00480] [00481] 45%  6g [00482] [00483] [00484] 40%  7g [00485] [00486] [00487] 21%  8g [00488] [00489] [00490] 35%  9g [00491] [00492] [00493] 46% 10g [00494] [00495] [00496] 39% 11g [00497] [00498] [00499] 51% 12g [00500] [00501] [00502] 49%

h) 2-[9-Phenyl-6-(9-phenylcarbazol-3-yl)carbazol-3-yl]spiro[fluorene-9,11-indolo[1,2-a]benzimidazole]

[0284] ##STR00503##

[0285] 6.36 g (16.3 mmol; 1.00 eq.) of 2-chlorospiro[fluorene-9,11′-indolo[1,2-a]benzimidazole], 11.4 g (18.7 mmol; 1.15 eq.) of 9,9′-diphenyl-6-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-9H,9′H-[3,3]bicarbazolyl [CAS 1572537-61-1] and 7.49 g (32.5 mmol; 2.00 eq.) of tripotassium phosphate [CAS 14593-46-5] are suspended in 210 ml of toluene [CAS 108-88-3] and 20 ml of water. To this suspension are added 334 mg (814 μmol; 5 mol %) of dicyclohexyl-(2′,6′-dimethoxybiphenyl-2-yl)phosphine (SPhos) [CAS 657408-07-6], 183 mg (814 μmol; 5 mol %) of palladium acetate [CAS 3375-31-3], and the reaction mixture is heated under reflux for 16 h. After cooling, the organic phase is removed, filtered through silica gel, washed three times with 150 ml of water and then concentrated to dryness. The residue is recrystallized from toluene and finally sublimed under high vacuum. The yield is 4.70 g (5.60 mmol, 34% of theory).

[0286] In an analogous manner, it is possible to obtain the following compounds:

TABLE-US-00010 No. Reactant 1 Reactant 2 Product Yield  1h [00504] [00505] [00506] 38%  2h [00507] [00508] [00509] 44%  3h [00510] [00511] [00512] 35%  4h [00513] [00514] [00515] 49%  5h [00516] [00517] [00518] 47%  6h [00519] [00520] [00521] 41%  7h [00522] [00523] [00524] 58%  8h [00525] [00526] [00527] 31%  9h [00528] [00529] [00530] 40% 10h [00531] [00532] [00533] 25%

i) 2-(4,6-diphenyl-1,3,5-triazin-2-yl)spiro[fluorene-9,11-indolo[1,2-a]benzimidazole]

[0287] ##STR00534##

[0288] 10.8 g (22.4 mmol; 1.20 eq.) of 2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)spiro[fluorene-9,11′-indolo[1,2-a]benzimidazole], 5.00 g (18.7 mmol; 1.00 eq.) of 2-chloro-4,6-diphenyl-[1,3,5]triazine and 8.58 g (39.2 mmol; 2.10 eq.) of tripotassium phosphate [CAS 14593-46-5] are suspended in 45 ml of toluene [CAS 108-88-3], 45 ml of dioxane [CAS 123-91-1] and 45 ml of water. To this suspension are added 383 mg (934 μmol; 5 mol %) of dicyclohexyl-(2′,6′-dimethoxybiphenyl-2-yl)phosphine (SPhos) [CAS 657408-07-6], 210 mg (934 μmol; 5 mol %) of palladium acetate [CAS 3375-31-3], and the reaction mixture is heated under reflux for 16 h. After cooling, the organic phase is removed, filtered through silica gel, washed three times with 500 ml of water and then concentrated to dryness. The residue is recrystallized from toluene [CAS 108-88-3] and finally sublimed under high vacuum. The yield is 5.32 g (9.05 mmol, 48% of theory).

[0289] In an analogous manner, it is possible to obtain the following compounds:

TABLE-US-00011 No. Reactant 1 Reactant 2 Product Yield 1i [00535] [00536] [00537] 55% 2i [00538] [00539] [00540] 63% 3i [00541] [00542] [00543] 36% 4i [00544] [00545] [00546] 45% 5i [00547] [00548] [00549] 56% 6i [00550] [00551] [00552] 39% 7i [00553] [00554] [00555] 43% 8i [00556] [00557] [00558] 59% 9i [00559] [00560] [00561] 66%

[0290] Production of the OLEDs

[0291] Examples I1 to I12 which follow (see Table 1) present the use of the materials of the invention in OLEDs.

[0292] Pretreatment for Examples I1-I12 Glass plaques coated with structured ITO (indium tin oxide) of thickness 50 nm are treated prior to coating with an oxygen plasma, followed by an argon plasma. These plasma-treated glass plaques form the substrates to which the OLEDs are applied.

[0293] The OLEDs basically have the following layer structure: substrate/hole injection layer (HIL)/hole transport layer (HTL)/electron blocker layer (EBL)/emission layer (EML)/optional hole blocker layer (HBL)/electron transport layer (ETL)/optional electron injection layer (EIL) and finally a cathode. The cathode is formed by an aluminium layer of thickness 100 nm. The exact structure of the OLEDs can be found in Table 1. The materials required for production of the OLEDs are shown in Table 2. The data of the OLEDs are listed in Table 3.

[0294] All materials are applied by thermal vapour deposition in a vacuum chamber. In this case, the emission layer always consists of at least one matrix material (host material) and an emitting dopant (emitter) which is added to the matrix material(s) in a particular proportion by volume by co-evaporation. Details given in such a form as EG1:IC2:TEG1 (49%:44%:7%) mean here that the material EG1 is present in the layer in a proportion by volume of 49%, 102 in a proportion of 44% and TEG1 in a proportion of 7%. Analogously, the electron transport layer may also consist of a mixture of two materials.

[0295] The OLEDs are characterized in a standard manner. For this purpose, the electroluminescence spectra, the current efficiency (CE, measured in cd/A) and the external quantum efficiency (EQE, measured in %) are determined as a function of luminance, calculated from current-voltage-luminance characteristics assuming Lambertian emission characteristics, as is the lifetime. The electroluminescence spectra are determined at a luminance of 1000 cd/m.sup.2, and the CIE 1931 x and y colour coordinates are calculated therefrom. The parameter U1000 in Table 3 refers to the voltage which is required for a luminance of 1000 cd/m.sup.2. CE1000 and EQE1000 respectively denote the current efficiency and external quantum efficiency that are attained at 1000 cd/m.sup.2.

[0296] The lifetime LT is defined as the time after which the luminance drops from the starting luminance to a certain proportion L1 in the course of operation with constant current density jo. A figure of L1=80% in Table 3 means that the lifetime reported in the LT column corresponds to the time after which the luminance falls to 80% of its starting value.

[0297] Use of Compounds of the Invention as Electron Transport Materials

[0298] The materials of the invention can be used in the electron transport layer (ETL) of OLEDs. The inventive compound EG1 can be used in examples I1, I2, I5 and I6 as electron transport material in fluorescent blue OLEDs. In addition, the materials of the invention can be used successfully in the hole blocker layer (HBL). This is shown in experiments 13, 14, 17 and 18.

[0299] Use of Compounds of the Invention as Matrix Materials in Phosphorescent OLEDs

[0300] The material of the invention can be used in the emission layer in phosphorescent, for example green, OLEDs. The inventive compounds EG1 to EG4 can be used in Examples I9 to I12 as matrix material in the emission layer.

TABLE-US-00012 TABLE 1 Structure of the OLEDs HIL HTL EBL EML HBL ETL EIL Ex. thickness thickness thickness thickness thickness thickness thickness I1 HATCN SpMA1 SpMA2 M2:SEB — EG1 LiQ 5 nm 195 nm 10 nm (95%:5%) 30 nm 3 nm 20 nm I2 HATCN SpMA1 SpMA2 M2:SEB — EG1:LiQ LiQ 5 nm 195 nm 10 nm (95%:5%) 30 nm 1 nm 20 nm I3 HATCN SpMA1 SpMA2 M2:SEB EG1 ST2 LiQ 5 nm 195 nm 10 nm (95%:5%) 10 nm 20 nm 3 nm 20 nm I4 HATCN SpMA1 SpMA2 M2:SEB EG1 ST2:LiQ LiQ 5 nm 195 nm 10 nm (95%:5%) 10 nm 20 nm 1 nm 20 nm I5 HATCN SpMA1 SpMA2 M2:SEB — EG2 LiQ 5 nm 195 nm 10 nm (95%:5%) 30 nm 3 nm 20 nm I6 HATCN SpMA1 SpMA2 M2:SEB — EG2:LiQ LiQ 5 nm 195 nm 10 nm (95%:5%) 30 nm 1 nm 20 nm I7 HATCN SpMA1 SpMA2 M2:SEB EG2 ST2 LiQ 5 nm 195 nm 10 nm (95%:5%) 10 nm 20 nm 3 nm 20 nm I8 HATCN SpMA1 SpMA2 M2:SEB EG2 ST2:LiQ LiQ 5 nm 195 nm 10 nm (95%:5%) 10 nm 20 nm 1 nm 20 nm I9 HATCN SpMA1 SpMA2 EG1:IC2:TEG1 ST2 ST2:LiQ LiQ 5 nm 230 nm 20 nm (49%:44%:7%) 10 nm (50%:50%) 1 nm 30 nm 30 nm I10 HATCN SpMA1 SpMA2 EG2:IC2:TEG1 ST2 ST2:LiQ LiQ 5 nm 230 nm 20 nm (49%:44%:7%) 10 nm (50%:50%) 1 nm 30 nm 30 nm I11 HATCN SpMA1 SpMA2 IC1:EG3:TEG1 ST2 ST2:LiQ LiQ 5 nm 215 nm 20 nm (59%:29%:12%) 10 nm (50%:50%) 1 nm 30 nm 30 nm I12 HATCN SpMA1 SpMA2 IC1:EG4:TEG1 ST2 ST2:LiQ LiQ 5 nm 195 nm 20 nm (59%:29%:12%) 10 nm (50%:50%) 1 nm 30 nm 30 nm

TABLE-US-00013 TABLE 2 Structural formulae of the materials for the OLEDs [00562] [00563] HATCN SpMA1 [00564] [00565] SpMA2 ST2 [00566] [00567] LiQ SEB [00568] [00569] M2 EG1 [00570] [00571] EG2 EG3 [00572] [00573] EG4 TEG1 [00574] [00575] IC1 IC2

TABLE-US-00014 TABLE 3 Data of the OLEDs EQE U1000 CE1000 1000 CIE x/y at j.sub.0 L1 LT Ex. (V) (cd/A) (%) 1000 cd/m.sup.2 (mA/cm.sup.2) (%) (h) I1 5.5 5 3.8 0.14/0.16 20 95 1040 I2 4.3 7 6.0 0.14/0.15 20 95 650 I3 4.8 7 5.5 0.14/0.16 20 95 200 I4 4.9 7 5.4 0.14/0.15 20 95 620 I5 5.3 6 4.4 0.14/0.16 20 95 950 I6 4.5 7 5.9 0.14/0.15 20 95 680 I7 4.7 7 5.6 0.14/0.16 20 95 420 I8 4.7 7 5.4 0.14/0.15 20 95 550 I9 3.2 62 16.9 0.36/0.61 20 80 730 I10 3.3 63 17.2 0.36/0.62 20 80 690 I11 3.3 64 17.4 0.35/0.62 20 80 450 I12 3.5 66 17.8 0.35/0.62 20 80 390

[0301] Thermal Stability

[0302] The inventive compound EG1, by comparison with the literature compound ST3, shows a distinct increase in thermal stability. This stability is determined by subjecting both materials to heat treatment in an evacuated glass ampoule at 350° C. for 7 days. Analytical determination of purity (HPLC) shows the following results:

TABLE-US-00015 [00576] [00577] EG1 ST3 Starting purity >99.9% >99.9% Purity after >99.9%  96.0% 7 d 350°