CATALYTIC ASYMMETRIC BORANE REDUCTION OF PROCHIRAL KETONES USING CHIRAL CAMPHOR-DERIVED MERCAPTO-ALCOHOLS

Easily available D-(+)-camphor-derived chiral mercapto-alcohols 2 and 3 were employed for catalytic asymmetric borane reduction of aromatic ketones. Moderate enantioselectivities with e.e. 20.2-72.1% were obtai ned with 10 mol% catalyst. Opposite asymmetric induction was achieved when mercapto-alcohols 2 and 3 were used.