Synthesis and structure of two platinum(II) complexes bearing N-heterocyclic carbene and dimethyl sulfoxide

Abstract

The reactions of cis-[PtCl₂(DMSO)₂] (1) with either 1,3-dibenzylimidazolium chloride (Bn₂-imyHCl) or 1,3- dibenzylbenzimidazolium chloride (Bn₂-bimy-HCl) in the presence of a base (Ag₂O/ Na₂CO₃/ CH₃COONa) afforded two mixed monocarbene-dimethyl sulfoxide (DMSO) complexes, namely d5-[PtCl₂(DMSO)(Bn₂-imy)] (2) and cis-[PtCl₂(DMSO)(Bn₂-bimy)] (3), with the high yields. The structures of 1˸3 were elucidated by Pt analysis, EDX, IR and H NMR spectra. The results show that the DMSO in 1˸3 coordinates with Pt(II) via the S atom, the deprotonated azolium salt is bound up with Pt(II) via the C atom (NCHN) and occupies cis-position in comparison with the DMSO in 2 and 3.