Facile Diastereoselective Reactions of Chiral 1,3-Oxazolidines with Grignard Reagents; Asymmetric Syntheses of 2-Substituted and 2,6-Disubstituted Piperidines

Abstract

a -(S)and (R)-2-Phenylpiperidines, (S)and (R)-2-methylpiperidines, mesoand (2K, 6R)-2,6-diphenylpiperidines, and mesoand (2S, 6s)-2,6dimethylpipendines were synthesized asymmetrically starting from the diastereoselective addition of Grignard reagents to chiral 1,3-oxazolidines, converting of 1- aza-4-oxabicyclo[4.3.O]nonane derivatives as pivotal intermediates.