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, LiLCS₂]. Mono-nuclear complexes of the type LCS₂]CuPR₃] 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]CuP(CH₂OH)₃]₂, where two phosphine co-ligands are coordinated to the copper(I) centre. The solid-state X-ray crystal structure of LCS₂]CuP(C₆H₅)₃] has been determined. The LCS₂]CuP(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.