Mono- and polynuclear complexes from the reaction of palladium acetate with α-substituted thioethers and thiols

Article abstract of DOI:10.1016/S0022-328X(98)00910-3

Palladium acetate reacts with α-substituted thioethers (RSCH(R′)Z; Z=ester, ketone, sulphone, substituted methyl) and the thiol HSCH₂C(O)Me to give complexes whose composition and nuclearity depend mainly on the electronic properties of the sulphur ligand. If it contains sufficiently acidic hydrogen atoms, the acetato group is partially or totally removed as acetic acid to give complexes of the type [Pd₃(μ-O₂CMe)₃(μ-RSCR′Z) ₃] and [Pd(SCH₂C(O)Me)₂]₆. The stability of the trimers decreases with the steric hindrance of the substituents at the sulphur and at the methine carbon atoms. Stable mixed sphere complexes are obtained also with carboxylato ligands different from acetato as PhCOO^- and MeSCH₂COO^-. When the substituted thioether has poor electronwithdrawing groups, its reaction with palladium acetate affords complexes of the type [Pd(η¹-OAc)₂(RSCH₂Z)₂], in which the sulphur donor atom has simply replaced one oxygen atom of the acetato ligand.