Complete Stereoselective Synthesis of Quasi-Enantiomeric Pseudo Imino-C-disaccharides: Parallel Kinetic Resolution of a Racemiccis-DihydroxypyrrolineN-Oxide by 1,2-Glycals

Abstract

Cycloadditions of hydroxylated enantiopure pyrroline N-oxides to 1,2-glycals display high double-asymmetric induction. The selectivity is controlled by the stereochemistry at C-3 of the glycal. A parallel kinetic resolution experiment with a racemic cis-dihydroxypyrroline N-oxide allowed the synthesis of two different pseudo imino-C-disaccharides precursors in a completely enantiopure form, totally avoiding the formation of minor cycloadducts.