Chemoenzymatic synthesis of azacycloalkan-3-ols

Optically active omega-bromocyanohydrins are easily synthesized through an enantioselective (R)-oxynitrilase-catalyzed reaction from their correspondi ng omega-bromoaldehydes. These cyanohydrins are starting materials for the preparation of medium size nitro gen heterocycles. The reduction of (R)-(+) -5-bromo-2-hydroxypentanenitrile affords, in one-pot, piperidin-3-ol. Azepa n-3-ol and azocan-3-ol are readily obtained from their corresponding cyanoh ydrins in high enantiomeric excesses. (C) 1999 Elsevier Science Ltd. All ri ghts reserved.