Binuclear metal complexes and electronic devices, in particular organic electroluminescent devices containing said metal complexes

A compound of formula (1):

• wherein
• M is the same or different in each instance and is iridium or rhodium;
• D is the same or different in each instance and is C or N, with the proviso that one C and one N are coordinated to each of the two M;
• X is the same or different in each instance and is CR or N;
• V is the same or different in each instance and is a group of formula (2) or (3):
• wherein one of the dotted bonds denotes the bond to the corresponding 6-membered aryl or heteroaryl group in formula (1) and the two other dotted bonds each denote the bonds to the sub-ligands L;
• L is the same or different in each instance and is a bidentate monoanionic sub-ligand;
• X1 is the same or different in each instance and is CR or N;
• A1 is the same or different in each instance and is C(R)2 or O;
• A2 is the same or different in each instance and is CR, P(═O), B, or SiR, with the proviso that, when A2=P(═O), B, or SiR, A1 is O and the A bonded to the A2 is not —C(═O)—NR′— or —C(═O)—O—;
• A is the same or different in each instance and is —CR═CR—, —C(═O)—NR′—, —C(═O)—O—, —CR2—CR2—, —CR2—O—, or a group of formula (4):
• wherein the dotted bond denotes the position of the bond of a bidentate sub-ligand L or the corresponding 6-membered aryl or heteroaryl group in formula (1) to this structure and * denotes the position of the linkage of the unit of formula (4) to the central cyclic group;
• X2 is the same or different in each instance and is CR or N or two adjacent X2 groups together are NR, O, or S, so as to define a five-membered ring, and the remaining X2 are the same or different in each instance and are CR or N;
• or two adjacent X2 groups together are CR or N when one of the X3 groups in the cycle is N, so as to define a five-membered ring;
• with the proviso that not more than two adjacent X2 groups are N;
• X3 is C in each instance or one X3 group is N and the other X3 groups in the same cycle are C;
• 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 in each instance and is H, D, F, Cl, Br, I, N(R1)2, CN, NO2, OR1, SR1, COOH, C(═O)N(R1)2, Si(R1)3, B(OR1)2, C(═O)R1, P(═O)(R1)2, S(═O)R1, S(═O)2R1, OSO2R1, COO(cation), SO3(cation), OSO3(cation), OPO3(cation)2, O(cation), N(R1)3(anion), P(R1)3(anion), 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, wherein the alkyl, alkenyl, or alkynyl group in each case is optionally substituted by one or more R1 radicals, wherein one or more nonadjacent CH2 groups are optionally 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 is optionally substituted in each case by one or more R1 radicals;
• and wherein two R radicals together optionally define a ring system;
• R′ is the same or different in each instance and is H, D, a straight-chain alkyl group having 1 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, wherein the alkyl group in each case is optionally substituted by one or more R1 radicals and wherein one or more nonadjacent CH2 groups are optionally replaced by Si(R1)2, or an aromatic or heteroaromatic ring system which has 5 to 40 aromatic ring atoms and is optionally substituted in each case by one or more R1 radicals;
• R1 is the same or different in each instance and is H, D, F, Cl, Br, I, N(R2)2, CN, NO2, OR2, SR2, Si(R2)3, B(OR2)2, C(═O)R2, P(═O)(R2)2, S(═O)R2, S(═O)2R2, OSO2R2, COO(cation), SO3(cation), OSO3(cation), OP3(cation)2, O(cation), N(R2)3(anion), P(R2)3(anion), 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, wherein the alkyl, alkenyl, or alkynyl group in each case is optionally substituted by one or more R2 radicals, wherein one or more nonadjacent CH2 groups are optionally 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 is optionally substituted in each case by one or more R2 radicals;
• wherein two or more R1 radicals together optionally define a ring system;
• R2 is the same or different in each instance and is H, D, F, or an aliphatic, aromatic, or heteroaromatic organic radical having 1 to 20 carbon atoms, wherein one or more hydrogen atoms is also optionally replaced by F;
• cation is the same or different in each instance and is selected from the group consisting of proton, deuteron, alkali metal ions, alkaline earth metal ions, ammonium, tetraalkylammonium, and tetraalkylphosphonium;
• and
• anion is the same or different in each instance and is selected from the group consisting of halides, carboxylates R2—COO−, cyanide, cyanate, isocyanate, thiocyanate, thioisocyanate, hydroxide, BF4−, PF6−, B(C6F5)4−, carbonate, and sulfonates.