Hydride transfer reactions catalysed by metal complexes

Abstract

Chloro-complexes of rhodium(III) catalyse the dehydrogenation of isopropyl alcohol to acetone. During the reaction rhodium metal is precipitated, and the rate of dehydrogenation decreases as rhodium is removed from solution. The reaction kinetics agree with the rate of evolution of hydrogen being proportional to the concentration of rhodium in solution. It is suggested that the catalysis proceeds via the reactions: Me₂CHOH +[Rh^IIICl]⇌ Me₂CO +[HRh^III]+ HCl, HCl +[HRh^III]→ H₂+[Rh^IIICl]