Materials for organic electroluminescent devices

A compound of the formula (1),

• where the following applies to the symbols and indices used:
• ArN is a group of the formula (2-2)
• V is, identically or differently, equal to CR6 or N;
• X is a divalent bridge selected from the group consisting of B(R0), C(R0)2, Si(R0)2, C═O, C═NR0, C═C(R0)2, O, S, S═O, SO2, P(R0) and P(═O)R0;
• or X is a group of the following formula (3),
• where the dashed bonds indicate the bonding to the 5-membered ring of formula (2-2);
• R0 is selected on each occurrence, identically or differently, from the group consisting of H, D, F, Cl, Br, I, CHO, CN, C(═O)Ar1, P(═O)(Ar1)2, S(═O)Ar1, S(═O)2Ar1, NO2, Si(R8)3, B(OR8), OSO2R8, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 40 C atoms, each of which is optionally substituted by one or more radicals R8, where in each case one or more non-adjacent CH2 groups is optionally replaced by R8C═CR8, C═C, Si(R8)2, Ge(R8)2, Sn(R8)2, C═O, C═S, C═Se, P(═O)(R8), SO, SO2, O, S or CONR8 and where one or more H atoms is optionally replaced by D, F, Cl, Br, I, CN or NO2, 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 Rs, an aryloxy group having 5 to 40 aromatic ring atoms, which is optionally substituted by one or more radicals R8, where two substituents R0 attached to the same C or Si atom may optionally form a mono- or polycyclic aliphatic ring system, which is optionally substituted by one or more radicals R8;
• with the proviso that when two R0 are attached to the same C atom, then at least one R0 is selected from the group consisting of H, D, F, CN, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 40 C atoms, each of which is optionally substituted by one or more radicals R8;
• R1, R2, R3, R4, R6 or R7 are selected on each occurrence, identically or differently, from the group consisting of H, D, F, Cl, Br, I, CHO, CN, C(═O)Ar1, P(═O)(Ar1)2, S(═O)Ar1, S(═O)2Ar1, NO2, Si(R8)3, B(OR8), OSO2R8, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 40 C atoms, each of which is optionally substituted by one or more radicals Rs, where in each case one or more non-adjacent CH2 groups is optionally replaced by R8C═CR8, C═C, Si(R8), Ge(R8)2, Sn(R8)2, C═O, C═S, C═Se, P(═O)(R8), SO, SO2, O, S or CONR8 and where one or more H atoms is optionally replaced by D, F, Cl, Br, I, CN or NO2, 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 R8, an aryloxy group having 5 to 40 aromatic ring atoms, which is optionally substituted by one or more radicals R8, where two or more adjacent substituents R1, two or more adjacent substituents R2, two or more adjacent substituents R3, two or more adjacent substituents R4, two or more adjacent substituents R6 or two or more adjacent substituents R7 may optionally form a mono- or polycyclic, aliphatic ring system or aromatic ring system, which is optionally substituted by one or more radicals R8;
• R5 is selected on each occurrence, identically or differently, from the group consisting of H, D, F, CN, a straight-chain alkyl or alkoxy group having 1 to 10 C atoms or a branched or cyclic alkyl or alkoxy or thioalkyl group having 3 to 10 C atoms, each of which is optionally substituted by one or more radicals R8, where one or more non-adjacent CH2 groups is optionally replaced by 0, and where one or more H atoms is optionally replaced by F;
• R8 is selected on each occurrence, identically or differently, from the group consisting of H, D, F, Cl, Br, I, CN, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 40 C atoms, where in each case one or more non-adjacent CH2 groups is optionally replaced by SO, SO2, O, S and where one or more H atoms is optionally replaced by D, F, Cl, Br or I, an aromatic or heteroaromatic ring system having 6 to 60 C atoms, where two or more adjacent substituents R8 may optionally form a mono- or polycyclic, aliphatic ring system;
• Ar1 is on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms, which may in each case also be substituted by one or more radicals R8;
• ArS is an aromatic ring system having 6 aromatic ring atoms, which may in each case also be substituted by one or more radicals R8;
• t, u are, identically or differently, 0 or 1;
• m, n, q, r are, identically or differently, 0, 1, 2, 3 or 4, where t+m≤4 and u+n≤4;
• p is 0, 1 or 2;
• i is 2;
• j is 1, 2 or 3;
• s is 0, 1, 2, 3, 4 or 5.