Isomerization of allylic alcohols to carbonyl compounds by aqueous-biphase rhodium catalysis

Abstract

Isomerization of allylic and homoallylic alcohols is catalyzed by the zwitterionic Rh(I) complex (sulphos)Rh(cod) in water–n-octane to give the corresponding aldehyde or ketone in high yields and chemoselectivity. A π-allyl metal hydride mechanism is proposed on the basis of various independent experiments in both homogeneous and biphasic systems [sulphos=−O₃S(C₆H₄)CH₂C(CH₂PPh₂)₃].