Reactions of organotin(IV) compounds with platinum complexes

Abstract

Organotin(IV) compounds SnRxCl4−x (R=Me, Ph; x=4−0) add oxidatively to [Pt(COD)2] (COD=cycloocta-1,5-diene) to yield platinum(II) complexes in which Pt has inserted into the SnCl or SnR bonds, displacing one COD entity. The new complexes react with tertiary phosphines, e.g. PEt3, PPh3, Ph2PCH2CH2PPh2 (DPPE) at or below room temperature with displacement of the remaining COD. Some of the resulting platinum–phosphine complexes, e.g. cis-[PtMe(SnMe3)(PPh3)2], cis- or trans-[PtCl(SnMe3)(PPh3)2] cannot be prepared by the direct reaction between [Pt(C2H4)(PPh3)2] or [Pt(PPh3)3] and SnMe4 or SnMe3CI, respectively, showing the advantage of this method. Both the COD complexes and their corresponding phosphine complexes were characterised by physical and spectroscopic methods. The thermodynamic stabilities of the complex [PtCl(SnMe3)(COD)], its corresponding phosphine complex, cis- and trans-[PtCl(SnMe3)(PPh3)2], and the complex cis-[PtMe(SnMe3)(PPh3)2] were studied.