title: Diastereoselectivity in epoxidation of carbohydrate fused [13]-macro-dilactones.
abstract: DMDO epoxidation of carbohydrate fused [13]-macro-dilactones was found to be highly diastereoselective. Facial selectivity of the epoxidation depended on the identity of the fused carbohydrate. Gluco-configured macro-dilactones gave the R, R epoxide, whereas the galacto- configuration gave the S, S epoxide. The epoxide stereochemisty was confirmed by independent syntheses of dimethyl 4 R,5R-epoxyoctanedioate via Shi epoxidation of dimethyl E-oct-4-enedioate and by transesterification of the epoxide derived from the gluco-[13]-macro-dilactone. We demonstrate diastereoselectivity in alkene reactivity driven by remote rather than adjacent stereocenters.
authors: Department of Chemistry, University of Connecticut,Storrs, Connecticut 06269, USA.
authors: W Sean
authors: WS
authors: Fyvie
authors: Mark W
authors: MW
authors: Peczuh