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-imy·HCl) 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 cis-[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 1H 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.