Ruthenium-catalysed synthesis of chiral exocyclic allylic alcohols via chemoselective transfer hydrogenation of 2-arylidene cycloalkanones

An asymmetric transfer hydrogenation of 2-arylidene four-, five-, six-, and seven-membered cycloalkanones under mild conditions has been performed. Various chiral exocyclic allylic alcohols were obtained by an exclusive reduction of CO bonds.