Metal complexes

A compound of the formula (1)

• where the symbols used are as follows:
• L1, L2, L3 are the same or different at each instance and are each a bidentate monoanionic sub-ligand that coordinates to the iridium via one carbon atom and one nitrogen atom, via two carbon atoms, via two nitrogen atoms, via two oxygen atoms or via one nitrogen atom and one oxygen atom;
• V is a group of the formula (2), where the dotted bonds each represent the position of linkage of the sub-ligands L1, L2 and L3,
• V1 is a group of the following formula (3):
• where the dotted bond represents the bond to L1 and * represents the bond to the central cycle in formula (2);
• V2 is selected from the group consisting of —CR2—CR2—,—CR2—SiR2—,—CR2—O—and —CR2—NR—, where these groups are each bonded to L2 and to the central cycle in formula (2);
• V3 is the same or different and is V1 or V2, where this group is bonded to L3 and to the central cycle in formula (2);
• X1 is the same or different at each instance and is CR or N;
• X2 is the same or different at each instance and is CR or N, or two adjacent X2 groups together are NR, O or S, thus forming a five-membered ring;
• or two adjacent X2 groups together are CR or N when one of the X3 groups in the cycle is N, thus forming a five-membered ring;
• with the proviso that not more than two adjacent X2 groups in each ring are N;
• X3 is C at each instance in the same cycle or one X3 group is N and the other X3 group in the same cycle is C, where the X3 groups may be selected independently when V contains more than one group of the formula (3);
• with the proviso that two adjacent X2 groups together are CR or N when one of the X3 groups in the cycle is N;
• R is the same or different at each instance and is H, D, F, Cl, Br, I, N (R1)2, OR1, SR1, CN, NO2, COOH, C(═O) N(R1)2, Si(R1)3, Ge(R1)3, B(OR1)2, C(═O)R1, P(═O)(R1)2, S(═O)R1, S(═O)2R1, OSO2R1, a straight-chain alkyl group having 1 to 20 carbon atoms or an alkenyl or alkynyl group having 2 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, where the alkyl, alkenyl or alkynyl group may in each case be substituted by one or more R1 radicals and where one or more nonadjacent CH2 groups may be replaced by Si(R1)2, C═O, NR1, O, S or CONR1, 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 R1 radicals;
• at the same time, two R radicals together may also form a ring system;
• R1 is the same or different at each instance and is H, D, F, Cl, Br, I, N (R2)2, OR2, SR2, CN, NO2, Si(R2)3, Ge(R2)3, B(OR2)2, C(═O)R2, P(═O)(R2)2, S(═O)R2, S(═O)2R2, OSO2R2, a straight-chain alkyl group having 1 to 20 carbon atoms or an alkenyl or alkynyl group having 2 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, where the alkyl, alkenyl or alkynyl group may in each case be substituted by one or more R2 radicals and where one or more nonadjacent CH2 groups may be replaced by Si(R2)2, C═O, NR2, O, S or CONR2, 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 R2 radicals;
• at the same time, two or more R1 radicals together may form a ring system;
• R2 is the same or different at each instance and is H, D, F or an aliphatic, aromatic and/or heteroaromatic organic radical having 1 to 20 carbon atoms, in which one or more hydrogen atoms may also be replaced by F;
• at the same time, the three bidentate ligands L1, L2 and L3, may also be closed by a further bridge to form a cryptate;
• and
• provided that none of V1, V2, V3, L1, L2, and L3 comprises a bicyclic group.