Materials for organic electroluminescent devices

A compound of formula (1)

• wherein
• Y is C(R1)2, CO, O, S, SO, SO2, NR3, PR3, or P(O)R3;
• X is CR1;
• A is on each occurrence, identically or differently, CR2 or N, where a maximum of three groups A in each ring are N;
• R1 and R2
• are on each occurrence, identically or differently, H, D, C, Br, I, F, CN, NO2, N(R4)3, Si(R4)3, B(OR4)2, C(═O)R4, P(═O)(R4)2, S(═O)R4, S(═O)2R4, —CR4═CR4—, OSO2R4, 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 are optionally substituted by one or more radicals R4, where one or more non-adjacent CH2 groups are optionally replaced by R4C═CR4, C≡C, Si(R4)2, Ge(R4)2, Sn(R4)2, C═O, C═S, C═Se, C═NR4, P(═O)(R4), SO, SO2, NR4, O, S or CONR4 and where one or more H atoms are optionally replaced by D, F, C, Br, I, CN or NO, or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which in each case is optionally substituted by one or more radicals R4, or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which is optionally substituted by one or more radicals R4, or aralkyl or heteroaralkyl group having 5 to 60 aromatic ring atoms, which are optionally substituted by one or more radicals R4;
• wherein two or more adjacent substituents R1 together with the atoms to which they are bonded or two or more adjacent substituents R2 together with the atoms to which they are bonded optionally define a mono- or polycyclic, aliphatic or aromatic ring system with one another;
• wherein at least one R1 which is bonded to X is triazine, which is optionally substituted by one or more radicals R4, or in that at least one R2 is a 6-membered heteroaromatic group, which is optionally substituted by one or more radicals R4, and at least one radical R1 simultaneously is an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which is optionally substituted by one or more radicals R4;
• R3 is on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 60 ring atoms, which in each case is optionally substituted by one or more radicals R4, or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which is optionally substituted by one or more radicals R3, or a combination of these systems;
• R4 is on each occurrence, identically or differently, H, D, F, Cl, Br, I, CN, NO2, N(R5)3, Si(R5)3, B(OR5)2, C(═O)R5, P(═O)(R5)2, S(═O)R5, S(═O)2R5, —CR5═CR5—, OSO2R5, 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 is optionally substituted by one or more radicals R5, where one or more non-adjacent CH2 groups are optionally replaced by R5C═CR5, C≡C, Si(R5)2, Ge(R5)2, Sn(R5)2, C═O, C═S, C═Se, C═NR5, P(═O)(R5), SO, SO2, NR5, O, S or CONR5 and where one or more H atoms may be replaced by D, F, C, Br, I, CN or NO2, or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which in each case are optionally substituted by one or more radicals R5, or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which are optionally substituted by one or more radicals R5, or aralkyl or heteroaralkyl group having 5 to 60 aromatic ring atoms, which are optionally substituted by one or more radicals R5;
• and wherein two or more radicals R4 optionally define a mono- or polycyclic, aliphatic or aromatic ring system with one another together with the atoms to which they are bonded;
• R5 is on each occurrence, identically or differently, an aliphatic, aromatic and/or heteroaromatic hydrocarbon radical having 1 to 20 C atoms;
• wherein two or more radicals R5 optionally define a mono- or polycyclic, aliphatic or aromatic ring system with one another together with the atoms to which they are bonded.