Materials for organic electroluminescent devices

1. A mixture comprising at least one compound of the formula (1) and at least one further compound

where

Y is C(R 1 ) 2 , O or NR 3 ;

X is on each occurrence, identically or differently, CR 1 or N, where a maximum of three groups X in each ring stand for N;

A is on each occurrence, identically or differently, CR 2 or N, where a maximum of three groups A in each ring stand for N;

R 1 , R 2 are on each occurrence, identically or differently, H, D, Cl, Br, I, F, CN, NO 2 , N(R 4 ) 3 , Si(R 4 ) 3 , B(OR 4 ) 2 , C(═O)R 4 , P(═O)(R 4 ) 2 , S(═O)R 4 , S(═O) 2 R 4 , —CR 4 ═CR 4 —, OSO 2 R 4 , a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 40 C atoms or an alkenyl or alkynyl group having 2 to 40 C atoms, each of which may be substituted by one or more radicals R 4 , where one or more non-adjacent CH 2 groups may be replaced by R 4 C═CR 4 , C≡C, Si(R 4 ) 2 , Ge(R 4 ) 2 , Sn(R 4 ) 2 , C═O, C═S, C═Se, C═NR 4 , P(═O)(R 4 ), SO, SO 2 , NR 4 , O, S or CONR 4 and where one or more H atoms may be replaced by D, F, Cl, Br, I, CN or NO 2 , 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 4 , or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R 4 , or aralkyl or heteroaralkyl group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R 4 ; two or more adjacent substituents R 1 together with the atoms to which they are bonded or two or more adjacent substituents R 2 together with the atoms to which they are bonded may also form a mono- or polycyclic, aliphatic or aromatic ring system with one another;

characterised in that at least one R 1 which is bonded to X stands for triazine, which may be substituted by one or more radicals R 4 ,

or in that at least one R 2 stands for a 6-membered heteroaromatic group, which may be substituted by one or more radicals R 4 , and at least one radical R 1 simultaneously stands for an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R 4 ;

R 3 is on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 60 ring atoms, which may in each case be substituted by one or more radicals R 4 , or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R 3 , or a combination of these systems;

R 4 is on each occurrence, identically or differently, H, D, F, Cl, Br, I, CN, NO 2 , N(R 5 ) 3 , Si(R 5 ) 3 , B(OR 5 ) 2 , C(═O)R 5 , P(═O)(R 5 ) 2 , S(═O)R 5 , S(═O) 2 R 5 , —CR 5 ═CR 5 —, OSO 2 R 5 , a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 40 C atoms or an alkenyl or alkynyl group having 2 to 40 C atoms, each of which may be substituted by one or more radicals R 5 , where one or more non-adjacent CH 2 groups may be replaced by R 5 C═CR 5 , C≡C, Si(R 5 ) 2 , Ge(R 5 ) 2 , Sn(R 5 ) 2 , C═O, C═S, C═Se, C═NR 5 , P(═O)(R 5 ), SO, SO 2 , NR 5 , O, S or CONR 5 and where one or more H atoms may be replaced by D, F, Cl, Br, I, CN or NO 2 , 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 5 , or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R 5 , or aralkyl or heteroaralkyl group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R 5 ; two or more radicals R 4 here may also form a mono- or polycyclic, aliphatic or aromatic ring system with one another together with the atoms to which they are bonded;

R 5 is on each occurrence, identically or differently, an aliphatic, aromatic and/or heteroaromatic hydrocarbon radical having 1 to 20 C atoms; two or more radicals R 5 here may also form a mono- or polycyclic, aliphatic or aromatic ring system with one another together with the atoms to which they are bonded.

2. The Mixture according to claim 1 , wherein the compound of formula (1) is selected from a compound of the formula (2), (3), (4), (5), (6), (7), (8), (9), (10), (11), (12), (13), (14) or (15):

where the symbols and indices used have the meanings indicated in claim 1 .

3. The mixture according to claim 1 , wherein, if at least one group R 1 stands for triazine, this is 1,3,5-triazine or 1,2,4-triazine, which may in each case be substituted by one or more radicals R 4 and where the radicals R 4 which are not equal to hydrogen or deuterium preferably stand for an aromatic or heteroaromatic ring system; or in that, if at least one group R 2 stands for a 6-membered heteroaromatic group, this is selected from triazine, pyrimidine, pyrazine, pyridazine or pyridine, each of which may be substituted by one or more radicals R 4 and where the radicals R 4 which are not equal to hydrogen or deuterium preferably stand for an aromatic or heteroaromatic ring system.

4. The mixture according to claim 1 , wherein the triazine substituents R 1 and R 2 and the pyrimidine substituents R 2 are selected from the groups depicted below:

where the dashed bond indicates the link from this group to the skeleton.

5. The mixture according to claim 1 , wherein the compound of formula (1) is a compound of the formula (16) or (17):

6. The mixture according to claim 1 , wherein the compound of formula (1) is selected from compounds of the formulae (20), (21), (24) or (25):

7. The mixture according to claim 1 , wherein the compound of formula (1) is a compound of formulae (29) or (31):

8. The mixture according to claim 1 , wherein the at least one further material is a matrix material.

9. The mixture according to claim 8 , wherein the matrix material is a hole transport material.

10. The mixture according to claim 1 further comprising a phosphorescent or fluorescent compound.

11. A formulation comprising at least one mixture according to claim 1 and one or more solvent.

12. An electronic devices comprising at least one mixture according to claim 1 , where the electronic device is selected from the group consisting of organic electroluminescent devices (OLEDs, PLEDs), organic field-effect transistors (O-FETs), organic thin-film transistors (O-TFTs), organic light-emitting transistors (O-LETs), organic integrated circuits (O-ICs), organic solar cells (O-SCs), organic field-quench devices (O-FQDs), light-emitting electrochemical cells (LECs), organic laser diodes (O-lasers) and organic photoreceptors.

13. The electronic device of claim 12 , wherein the device is an organic electroluminescent device.