Access to pyrrolidineimino sugarsvia tin(ii)-mediated aldol reactions of bislactim ethers: synthesis of 2,5-dideoxy-2,5-imino-d-glucitol

Abstract

2,5-Dideoxy-2,5-imino-D-glucitol (DGDP) has been synthesized via the tin(II)-mediated anti-selective aldol reaction of bislactim ether 5 and a 3-O-silylated 2,4-ethylidene-D-erythrose derivative 6. In accordance with density functional theory calculations (at the B3LYP/cc-pVDZ-PP level), pericyclic transition structures with a boat-like conformation and a stabilizing hydrogen bond can account for the unexpected stereoselectivity.