The first highly diastereo- and enantioselective polymeric catalyst for the 1,3-cycloaddition reaction of nitrones with alkenes
Abstract
A highly diastereo- and enantioselective 1,3-dipolar cycloaddition reaction of nitrones with alkenes catalyzed by chiral polybinaphthyl Lewis acids has been developed giving isoxazolidines with up to 99% ee; the chiral polymer ligand shows almost identical stereoselectivity to its monomeric version but has the advantage of easy recovery and reuse, and this work further demonstrates that a rigid and sterically regular polymer chain can be used to preserve the catalytic properties of monomeric catalysts.