Fine tuning of chemo- and stereo-selectivity in cyclization reactions of tethered radicals derived from 4-O-substituted-α-D-erythro-oct-2,6-dienopyranosides. Stereoselective access to carbocycles and branched-chain sugars
Abstract
Chemoselectivity in the radical cyclization of tethered α-D-erythro-oct-2,6-dienopyranosides can be accomplished by changes in the nature of the tether and/or in the oxidation state at the termini of the olefins, to afford stereoselectively 3-deoxy-3-C-substituted carbohydrates, off-template branched-chain sugars, or functionalized cyclopentanes.