Sn2' regio and stereoselective alkylation of allylic mesylates linked to a N-Boc oxazolidine using organocuprates

Article abstract of DOI:10.1016/S0040-4039(99)00800-X

N-Boc-oxazolidines bearing an allylic alcohol chain were transformed into their mesylate derivatives. A regio and stereoselective 1,3-transfer of chirality was effected on these mesylates during their alkylation by mean of organocuprate additions. The resulting N-Boc-2-alkenyl oxazolidines undergo an intramolecular bromocarbamoylation with a high level of stereocontrol upon treatment with bIBS and afford, after treatment with sodium ethoxide, the corresponding epoxy oxazolidines. The overall methodology allows an efficient control for the formation of three contiguous chiral centers.