Organosilyl and organogermyl complexes of platinum(II)

Abstract

The preparation of trimethylsilyl and trimethylgermyl complexes of platinum(II) of the type trans-(Et₃P)₂Pt(MMe₃)Cl (M = Si and Ge) from (Me₃M)₂Hg and cis-(Et₃P)₂PtCl₂ is described. Several reactions are reported involving both chloride ion replacement (Br^–, I^–, CN^–, NCS^–, Ph^–, and GePh₃^–) and cleavage of the Pt–M bond [H₂O, PhC⋮CH, (CH₂Cl)₂, and H₂]. The hydrogenation at 1 atmosphere has been studied in some detail, and both the Me₃Ge and the Me₃Si groups are cleaved in preference to the Ph₃Ge group in the complexes trans-(Et₃P)₂Pt(MMe₃)(GePh₃) Infrared and ¹H n.m.r. spectroscopy have been used to determine the stereochemistry of these complexes. Platinum–silicon, –phosphorus, and –chlorine stretching frequencies have been assigned. In cis-complexes, e.g., (Et₃P)₂PtPh(GeMe₃), a unique long-range coupling between the Me₃Ge protons and the trans-³¹P nucleus is observed. The mass spectrum of trans-(Et₃P)₂Pt(GeMe₃)Cl is described.