Metal complexes

A compound of the formula (1),

• where the following applies to the symbols used:
• M is a transition metal;
• A is N, P, B, C− or CR;
• Y is on each occurrence, identically or differently, CR2, NR, O S or a single bond, where a maximum of one group Y stands for a single bond;
• Z is on each occurrence, identically or differently, C or N, with the proviso that both Z stand for C if Ar3 stands for an aromatic or heteroaromatic six-membered ring, and that either both Z stand for C or one Z stands for C and the other Z stands for N if Ar3 stands for a heteroaromatic five-membered ring;
• D is on each occurrence, identically or differently, C or N;
• Ar1 is on each occurrence, identically or differently, together with the group D and the three carbon atoms explicitly drawn in, one carbon bonded to Y, one carbon bonded to A and one carbon bonded to Ar2, an aryl or heteroaryl group having 5 to 13 aromatic ring atoms, which is optionally substituted by one or more radicals R1;
• Ar2 is on each occurrence, identically or differently, together with the group D and the carbon atom explicitly drawn in, and bonded to Ar1, an aryl or heteroaryl group having 5 to 13 aromatic ring atoms, which is optionally substituted by one or more radicals R1;
• Ar3 is, together with the two groups Z and the carbon atom, an aryl or heteroaryl group having 5 to 10 aromatic ring atoms, which is optionally substituted by one or more radicals R1;
• R and R1 is on each occurrence, identically or differently, H, D, F, Cl, Br, I, N(R2)2, CN, NO2, OH, COOH, C(═O)N(R2)2, Si(R2)3, B(OR2)2, C(═O)R2, P(═O)(R2)2, S(═O)R2, S(═O)2R2, OSO2R2, a straight-chain alkyl, alkoxy or thioalkoxy 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, alkoxy or thioalkoxy group having 3 to 20 C atoms, each of which is optionally substituted by one or more radicals R2, where one or more non-adjacent CH2 groups is optionally replaced by R2C═CR2, C≡C, Si(R2)2, C═O, NR2, O, S or CONR2 and where one or more H atoms is optionally replaced by D, F, Cl, Br, I or CN, or an aromatic or hetero-aromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R2, or an aryloxy or heteroaryloxy group having 5 to 40 aromatic ring atoms, which is optionally substituted by one or more radicals R2, or an aralkyl or heteroaralkyl group having 5 to 40 aromatic ring atoms, which is optionally substituted by one or more radicals R2, or a diarylamino group, diheteroarylamino group or arylheteroarylamino group having 10 to 40 aromatic ring atoms, which is optionally substituted by one or more radicals R2;
• two adjacent radicals R or two adjacent radicals R1 here may also form a mono- or polycyclic, aliphatic or aromatic ring system with one another;
• furthermore, the radicals R1 which are bonded to adjacent groups Ar1 and Ar2 may also form a mono- or polycyclic, aliphatic or aromatic ring system with one another;
• R2 is on each occurrence, identically or differently, H, D, F, Cl, Br, I, N(R3)2, CN, NO2, Si(R3)3, B(OR3)2, C(═O)R3, P(═O)(R3)2, S(═O)R3, S(═O)2R3, OSO2R3, a straight-chain alkyl, alkoxy or thioalkoxy 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, alkoxy or thioalkoxy group having 3 to 20 C atoms, each of which is optionally substituted by one or more radicals R3, where one or more non-adjacent CH2 groups is optionally replaced by R3C═CR3, C≡C, Si(R3)2, C═O, NR3, O, S or CONR3 and where one or more H atoms is optionally replaced by D, F, Cl, Br, I, CN or NO2, 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 R3, or an aryloxy or heteroaryloxy group having 5 to 40 aromatic ring atoms, which is optionally substituted by one or more radicals R3, or an aralkyl or heteroaralkyl group having 5 to 40 aromatic ring atoms, which is optionally substituted by one or more radicals R3, or a diarylamino group, diheteroarylamino group or arylheteroarylamino group having 10 to 40 aromatic ring atoms, which is optionally substituted by one or more radicals R3;
• R3 is on each occurrence, identically or differently, H, D, F or an aliphatic or aromatic hydrocarbon radical having 1 to 20 C atoms, in which, in addition, one or more H atoms is optionally replaced by F;
• two or more substituents R3 here may also form a mono- or polycyclic, aliphatic ring system with one another.