Chiral Silver Phosphate Catalyzed Transformation of <i>ortho</i>‐Alkynylaryl Ketones into 1<i>H</i>‐Isochromene Derivatives through an Intramolecular‐Cyclization/Enantioselective‐Reduction Sequence

Abstract

The transformation of ortho-alkynylaryl ketones through a cyclization/enantioselective-reduction sequence in the presence of a chiral silver phosphate catalyst afforded 1H-isochromene derivatives in high yield with fairly good to high enantioselectivity. An asymmetric synthesis of the 9-oxabicyclo[3.3.1]nona-2,6-diene framework, which has been found in some biologically active molecules, is presented as a demonstration of the synthetic utility of this method.