Asymmetric domino 1,6-addition/annulation reaction of 3-cyano-4-alkenyl-2<i>H</i>-chromen-2-ones with isatin-derived MBH carbonates: enantioselective synthesis of 3,3′-cyclopentenylspirooxindoles bearing 2<i>H</i>-chromen-2-ones

Abstract

An asymmetric domino 1,6-addition/annulation reaction of 3-cyano-4-alkenyl-2<italic>H</italic>-chromen-2-ones with isatin-derived MBH carbonates was achieved by using a modified cinchona alkaloid as a catalyst.