Preparation, structures, and reactions of some difluorothiophosphonate and difluoroselenophosphonate complexes of platinum(II)

Abstract

The complexes [Pt(PEt₃)₂(PF₂Y)X](X = Cl, Br, or I; Y = S or Se) have been prepared by the reaction of trans-[PtH(PEt₃)₂X] with PF₂H(Y). The reactions have been studied at low temperatures using ³¹P and ¹⁹F n.m.r. spectroscopy; the formation of [Pt^IVH₂(PEt₃)₂(PF₂Y)X] and [Pt^IIH(PEt₃)₂(PF₂Y)] as intermediates was observed, and a mechanism has been proposed. The complexes [Pt(PEt₃)₂(PF₂Y)X](X = H, Cl, Br, or l) were also prepared by reaction of [Pt(PEt₃)₃X][BPh₄] with PF₂H(Y): the hydride complexes were stable at room temperature. The X-ray crystal structure was obtained for trans-[PtCl(PEt₃)₂(PF₂S)]. The crystals are orthorhombic, space group Pbcn, with a= 1.1597(2), b= 1.3355(2), and c= 1.3632(3) nm. The structure has been solved with 934 diffractometer data and refined with 876 data to R= 0.034. The molecules are packed with a two-fold disorder about the Pt–Cl bond, but the two positions of the PF₂S moiety are clearly resolved.