Chiral induction in lanthanide(III)‐alkoxide‐catalysed Meerwein‐Ponndorf‐Verley reductions

The reduction of acetophenone using a chiral catalyst, prepared in situ by adding a chiral dihydroxy compound to a solution of a lanthanide(III) alkoxide, was studied. The highest enantiomeric excess (ee) (32%) was observed with La(O′Bu) 3 as the catalyst and 1,2:5,6‐di‐ O ‐isopropylidene‐D‐mannitol as the chiral ligand. With pinacolone as the substrate, an ee of 22% was obtained.