A series of 3-substituted piperidines in enantiomerically pure form has been synthesized from lactam 1 via the bromo derivative 2i. t-Butyl acetate and 5-methylpyridine derivatives 2g and 2h were obtained optically pure by direct alkylation of 1 with corresponding halides. Azido, amino or benzyloxy products were obtained by diastereoselective substitution of 2i. Copyright (C) 1996 Elsevier Science Ltd