DECARBONYLATION OF ACYLCHLOROBIS-(TRIPHENYLPHOSPHINE) PLATINUM(II) COMPLEXES PROMOTED BY TIN(II) CHLORIDE

Abstract
While it might be expected that the availability of vacant coordination sites in the four coordinate acyl complexes trans[Pt(PPh3)2 (RCO)Cl] provides low energy pathways for alkyl and aryl migration and subsequent decarbonylation, the decarbonylation has been previously achieved only at elevated temperatures. The addition of SnCl2 greatly facilitates decarbonylation of [Pt(PPh3)2 (RCO)Cl] where R is CH3, C2 H5, Y[sbnd]C6 H4. Compounds of the type [Pt(PPh3)2 (RCO)SnCl3] and [Pt(PPh3)2 R(SnCl3)] have been isolated. The removal of SnCl2 from these compounds has been achieved with ethanol. A kinetic study of the decarbonylation of [Pt(PPh3)2 (RCO)SnCl3] (where R is CH3, C2 H5, Y[sbnd]C6 H4 for Y=H, CH3, CH3 O, NO2, Cl) is reported. The role of 3 and 5 coordinate intermediates in alkyl-aryl migrations in Pt(II) systems is discussed.