chirality wiley

asymmetric hydrogenation

functional group

chiral

highly stereoselective

stereoselective synthesis

asymmetric synthesis

enantiomerically pure

furans

kinetic resolution

Journal of the American Chemical Society

We report a new method for stereoselective <i>O</i>-furanosylation reactions promoted by a precisely tailored bis-thiourea hydrogen-bond-donor catalyst. Furanosyl donors outfitted with an anomeric dialkylphosphate leaving group undergo substitution with high anomeric selectivity, providing access to the challenging 1,2-<i>cis</i> substitution pattern with a range of alcohol acceptors. A variety of stereochemically distinct, benzyl-protected glycosyl donors were engaged successfully as substrates. Mechanistic studies support a stereospecific mechanism in which rate-determining substitution occurs from a catalyst-donor resting-state complex.

Stereospecific Furanosylations Catalyzed by Bis-thiourea Hydrogen-Bond Donors