Reactions of α,β-unsaturated thioesters with platinum(0):: Implication of a dual mechanism leading to the formation of acyl platinum

The moderate reactivity of the alpha,beta-unsaturated thioester (ArS) C(O) C(A)-C(B)(H) toward Pt(PPh3)(2)( C2H4) has been used to extract thermodynamic and kinetic information pertaining to the oxidative addition of alpha,beta-unsaturated acid halide derivatives to low-valent transition-metal complexes. The results indicate acyl platinum product complexes can form by direct C-S bond cleavage or by attack of coordinated Pt(PPh3)(2) on the beta-carbon.