Process for preparing ortho-metallated metal compounds

A process for preparing metal complexes of formula (1)

• wherein
• M is Rh, Ir, Pd, or Pt;
• DCy is on each occurrence, identically or differently, a cyclic group optionally substituted with R and which comprises at least one neutral donor atom via which DCy is bonded to M;
• CCy is on each occurrence, identically or differently, a cyclic group optionally substituted with R which comprises a carbon atom or a negatively charged nitrogen atom via which CCy is bonded to M;
• wherein the bond between DCy and CCy is a covalent bond, and wherein DCy and CCy are optionally further connected to each other via a radical R;
• R is on each occurrence, identically or differently, F, Cl, Br, I, NO2, CN, NH2, NHR1, N(R1)2, B(OH)2, B(OR1)2, CHO, COOH, CONH2, CON(R1)2, SO3H, C(═O)R1, P(═O)(R1)2, S(═O)R1, S(═O)2R1, P(R1)3+, N(R1)3+, OH, SH, a straight-chain alkyl or alkoxy group having up to 20 C atoms or a branched or cyclic alkyl or alkoxy group having 3 to 20 C atoms, each optionally substituted by one or more groups R2, wherein in each instance one or more non-adjacent CH2 groups are optionally replaced by —O—, —S—, —NR1—, —CONR1—, —CO—O—, —CR1═CR1— or —C≡C—, an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, optionally substituted by one or more radicals R2, or an aryloxy, heteroaryloxy, arylamino, or heteroarylamino group having 5 to 30 aromatic ring atoms, optionally substituted by one or more radicals R2;
• wherein two or more substituents R, either on the same ring or on the two different rings, optionally define a further mono- or polycyclic, aliphatic or aromatic ring system with one another or with R1, R2, and/or R3;
• R1 is on each occurrence, identically or differently, H, a straight-chain alkyl group having up to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, each optionally substituted by one or more groups R2, wherein in each instance one or more non-adjacent CH2 groups which are not bonded directly to a heteroatom are optionally replaced by —O—, —S—, —NR3—, —CONR3—, —CO—O—, —CR3═CR3— or —C≡C—, or an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, optionally substituted by one or more radicals R3;
• and wherein two or more substituents R1 optionally define a further mono- or polycyclic, aliphatic or aromatic ring system with one another or with R, R2, and/or R3;
• R2 is on each occurrence, identically or differently, H, F, Cl, Br, I, NO2, CN, NH2, NHR3, N(R3)2, B(OH)2, B(OR3)2, CHO, COOH, CON(R3)2, SO3H, C(═O)R1, P(═O)(R1)2, S(═O)R1, S(═O)2R1, P(R3)3+, N(R3)3+, OH, SH, a straight-chain alkyl or alkoxy group having up to 20 C atoms or a branched or cyclic alkyl or alkoxy group having 3 to 20 C atoms, each optionally substituted by one or more groups R3, wherein in each instance one or more non-adjacent CH2 groups are optionally replaced by —O—, —S—, —NR3—, —CONR3—, —CO—O—, —CR3═CR3— or —C≡C—,
• or an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, optionally substituted by one or more radicals R3, or an aryloxy, heteroaryloxy, arylamino, or heteroarylamino group having 5 to 30 aromatic ring atoms, optionally substituted by one or more radicals R3;
• wherein two or more substituents R2, either on the same ring or on the two different rings, optionally define a further mono- or polycyclic, aliphatic or aromatic ring system with one another or with R, R1, and/or R3;
• R3 is, identically or differently on each occurrence, H or an aliphatic or aromatic hydrocarbon radical having up to 20 C atoms, wherein two or more radicals R3 optionally define a ring system with one another;
• m is 2 when M is Pd or Pt and is 3 when M is Rh or Ir;
• comprising reacting a metal compound of formula (2), (3), or (4)
• MXm*zH2O*yHX Formula (2)
• Yn[MXp]*zH2O*yHX Formula (3)
• wherein M and m are as defined above, and
• wherein
• X is on each occurrence, identically or differently, F, Cl, Br, or I;
• Y is on each occurrence, identically or differently, an alkali metal cation, an alkaline earth metal cation, an ammonium cation, a tetraalkylammonium cation having 4 to 40 C atoms, or a tetraalkylphosphonium cation having 4 to 40 C atoms;
• p is 4 when M is Pd or Pt and is 6 when M is Rh or Ir;
• n is the charge of M for a monovalent cation Y and is half the charge of M for a divalent cation Y;
• z is an integer from 0 to 100;
• y is an integer from 0 to 100;
• with a compound of formula (5)
• wherein DCy and CCy are as defined above;
• and
• wherein said reaction is carried out (1) in the presence of a salt whose anion contains at least two oxygen atoms and (2) in a solvent mixture comprising at least one organic solvent and at least 2% by volume of water
• wherein said salt is an alkali metal, alkaline earth metal, ammonium, tetraalkylammonium, tetraalkylphosphonium, and/or tetraarylphosphonium salt of carbonate, hydrogencarbonate, sulfate, hydrogensulfate, sulfite, hydrogensulfite, nitrate, nitrite, phosphate, hydrogenphosphate, dihydrogenphosphate, or borate;
• an alkali metal, alkaline earth metal, ammonium, tetraalkylammonium, tetraalkylphosphonium, and/or tetraarylphosphonium salt of organic carboxylic acids having up to 20 C atoms, organic sulfonic acids having up to 20 C atoms, α-ketocarboxylates, β-ketoketonates, β-ketocarboxylates;
• salts of pyrocatechol and salicylic acid;
• an aminocarboxylic acid;
• an aromatic aminocarboxylic acid;
• an polyaminocarboxylic acid;
• an N-alkylated amino-carboxylic acid, wherein said alkyl groups contain up to 10 C atoms;
• an aminosulfonic acid or N-alkylated aminosulfonic acid, wherein said alkyl groups contain up to 10 C atoms;
• or salts of these compounds which are obtained by abstraction of one or more protons.