Isoquinoline-based diimine ligands for Cu(II)-catalyzed enantioselective nitroaldol (Henry) reactions

Abstract

A series of isoquinoline-based chiral diimine ligands are conveniently prepared via Bischler–Napieralski cyclization. The C 2-symmetric diimine ligand 1a is effective in Cu(II)-catalyzed enantioselective Henry reactions between nitromethane and various aldehydes (11 examples), showing 50–89% yield and 75–93% ee.