A highly stereoselective and recyclable microgel-supported bifunctional sulfonamide organocatalyst for asymmetric alcoholysis of meso-cyclic anhydrides: a thermo-responsive “organic nanoreactor”†
Abstract
A novel thermosensitive bifunctional sulfonamide microgel catalyst was synthesized by immobilization on a highly cross-linked three-dimensional network structure through covalent interactions. The microgel-supported organocatalyst has been successfully applied to catalyze the asymmetric alcoholysis reaction in high yields and good stereoselectivity (up to 90% ee). Furthermore, the polymeric catalysts could be recovered easily and reused multiple times (5 runs) without apparent loss of catalytic activity and enantioselectivity.