Metal complexes

A monometallic metal complex comprising a hexadentate tripodal ligand wherein three bidentate sub-ligands coordinate to a metal and the three bidentate sub-ligands, which are optionally the same or different, are joined via a bridge of formula (1):

• wherein
• the dotted bonds represent the bonds of the three bidentate sub-ligands to this structure;
• X1 is the same or different in each instance and is C, which is optionally substituted, or N;
• X2 is the same or different in each instance and is C, which is optionally substituted, or N;
• or two adjacent X2 groups together are N, which is optionally substituted, O or S, so as to form a five-membered ring;
• or two adjacent X2 groups together are C, which is optionally substituted, or N when one of the X3 groups in the cycle is N, so as to form a five-membered ring;
• with the proviso that not more than two adjacent X2 groups in each ring are N;
• and wherein any substituents optionally define a ring system with one another or with substituents bonded to X1;
• X3 is C in each instance in one cycle or one X3 group is N and the other X3 group in the same cycle is C, wherein the X3 groups in the three cycles are optionally selected independently, with the proviso that two adjacent X2 groups together are C, which is optionally substituted, or N when one of the X3 groups in the cycle is N;
• and
• wherein the three bidentate ligands, apart from via the bridge of formula (1), are optionally ring-closed by a further bridge to form a cryptate, and
• wherein at least one of the bidentate sub-ligands is a structure of formulae (L-1), (L-2), (L-3), (L-4), (L-33), (L-34), (L-41), (L-42), (L-43) or (L-44):
• wherein
• the dotted bond represents the bond of the sub-ligand to the bridge of formula (1);
• CyC is the same or different in each instance and is a substituted or unsubstituted aryl or heteroaryl group which has 5 to 14 aromatic ring atoms and coordinates to the metal via a carbon atom in each case and which is bonded to CyD in (L-1) and (L-2) via a covalent bond and is bonded to a further CyC group in (L-4) via a covalent bond;
• CyD is the same or different in each instance and is a substituted or unsubstituted heteroaryl group which has 5 to 14 aromatic ring atoms and coordinates to the metal via a nitrogen atom or via a carbene carbon atom and which is bonded to CyC in (L-1) and (L-2) via a covalent bond and is bonded to a further CyD group in (L-3) via a covalent bond;
• and
• wherein two or more of the optional substituents together optionally define a ring system;
• wherein
• R is the same or different in each instance and is H, D, F, Cl, Br, I, N(R1)2, CN,
• NO2, OH, 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, a straight-chain alkyl, alkoxy, or thioalkoxy 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, alkoxy, or thioalkoxy group having 3 to 20 carbon atoms, wherein the alkyl, alkoxy, thioalkoxy, alkenyl, or alkynyl group is optionally substituted by one or more R1 radicals and wherein one or more nonadjacent CH2 groups are optionally replaced by R1C═CR1, C≡C, Si(R1)2, C═O, NR1, O, S, or CONR1, 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, or an aryloxy or heteroaryloxy group which has 5 to 40 aromatic ring atoms and is optionally substituted by one or more R1 radicals;
• and wherein two R radicals together optionally define a ring system;
• R1 is the same or different in each instance and is H, D, F, Cl, Br, I, N(R2)2, CN, NO2, 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 carbon atoms or an alkenyl or alkynyl group having 2 to 20 carbon atoms or a branched or cyclic alkyl, alkoxy, or thioalkoxy group having 3 to 20 carbon atoms, wherein the alkyl, alkoxy, thioalkoxy, alkenyl, or alkynyl group is optionally substituted by one or more R2 radicals and wherein one or more nonadjacent CH2 groups are optionally replaced by R2C═CR2, C≡C, Si(R2)2, C═O, NR2, O, S, or CONR2, 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, or an aryloxy or heteroaryloxy group which has 5 to 40 aromatic ring atoms and is optionally substituted by one or more R2 radicals;
• and 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, and/or heteroaromatic organic radical having 1 to 20 carbon atoms, in which one or more hydrogen atoms may also be replaced by F;
• * represents the position of coordination to the metal;
• O represents the position of a bond to the group of the formula (1);
• and
• X is the same or different at each instance and is CR or N, with the proviso that not more than one X symbol per cycle is N;
• wherein
• the sub-ligands (L-41) to (L-43) each coordinate to the metal via the nitrogen atom explicitly shown and the negatively charged oxygen atom, and the sub-ligand (L-44) coordinates via the two oxygen atoms;
• X is the same or different in each instance and is CR or N, with the proviso that not more than two X per cycle are N;
• R is the same or different in each instance and is H, D, F, Cl, Br, I, N(R1)2, CN, NO2, OH, 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, a straight-chain alkyl, alkoxy, or thioalkoxy 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, alkoxy, or thioalkoxy group having 3 to 20 carbon atoms, wherein the alkyl, alkoxy, thioalkoxy, alkenyl, or alkynyl group is optionally substituted by one or more R1 radicals and wherein one or more nonadjacent CH2 groups are optionally replaced by R1C═CR1, C≡C, Si(R1)2, C═O, NR1, O, S, or CONR1, 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, or an aryloxy or heteroaryloxy group which has 5 to 40 aromatic ring atoms and is optionally substituted by one or more R1 radicals;
• and wherein two R radicals together optionally define a ring system;
• R1 is the same or different in each instance and is H, D, F, Cl, Br, I, N(R2)2, CN, NO2, 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 carbon atoms or an alkenyl or alkynyl group having 2 to 20 carbon atoms or a branched or cyclic alkyl, alkoxy, or thioalkoxy group having 3 to 20 carbon atoms, wherein the alkyl, alkoxy, thioalkoxy, alkenyl, or alkynyl group is optionally substituted by one or more R2 radicals and wherein one or more nonadjacent CH2 groups are optionally replaced by R2C═CR2, C≡C, Si(R2)2, C═O, NR2, O, S, or CONR2, 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, or an aryloxy or heteroaryloxy group which has 5 to 40 aromatic ring atoms and is optionally substituted by one or more R2 radicals;
• and 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, and/or heteroaromatic organic radical having 1 to 20 carbon atoms, in which one or more hydrogen atoms may also be replaced by F and
• o indicates the position of a bond to the group of the formula (1).