Copper(I)–organophosphine complexes of bis(3,5-dimethylpyrazol-1-yl)dithioacetate ligand

Copper(I) complexes have been synthesized from the reaction of CuCl, monodentate tertiary phosphines PR3 (PR3 = P(C6H5)3; P(C6H5)2(4-C6H4COOH); P(C6H5)2(2-C6H4COOH); PTA, 1,3,5-triaza-7-phosphaadamantane; P(CH2OH)3, tris(hydroxymethyl)phosphine) and lithium bis(3,5-dimethylpyrazolyl)dithioacetate, Li[LCS2]. Mono-nuclear complexes of the type [LCS2]Cu[PR3] have been obtained and characterized by elemental analyses, FT-IR, ESI-MS and multinuclear (1H, 13C and 31P) NMR spectral data; in these complexes the ligand behaves as a κ3-N,N,S scorpionate system. One exception to this stoichiometry was observed in the complex [LCS2]Cu[P(CH2OH)3]2, where two phosphine co-ligands are coordinated to the copper(I) centre. The solid-state X-ray crystal structure of [LCS2]Cu[P(C6H5)3] has been determined. The [LCS2]Cu[P(C6H5)3] complex has a pseudo tetrahedral copper site where the bis(3,5-dimethylpyrazolyl)dithioacetate ligand acts as a κ3-N,N,S donor.