Disproportionation of a halogen-bridged complex containing platinum and palladium

Abstract

31 P N.m.r. spectroscopy shows that complexes of the type [PdPtCl4LaLb][Laand Lb are either the same or different tertiary-phosphide ligands (PPr3 or Pbu3)] are formed in chloroform solution when equimolar amounts of [Pd2Cl4(La)2] and [Pt2Cl4(Lb)2] are mixed at room temperature. All three complexes are in dynamic equilibrium, and a kinetic study indicates that the exchange occurs via a tetrameric intermediate involving four metal centres. Attempts to isolate the mixed metal complexes have proved unsuccessful. The first measurement of platinum–platinum coupling constants is reported for the complexes [Pt2Cl4(PBu3)2] and [Pt2I4(Pbu3)2].