Enantioselective Propargylation and Allenylation of Isatins Using Chiral Box-Copper/Zinc Catalysts

A method for the asymmetric propargylation and allenylation of isatins catalyzed using chiral Box-copper/zinc catalysts is described. By modulation of the metal and solvent, a series of chiral 3-hydroxy-3-propargyl-2-oxindoles and 3-hydroxy-3-allenyl-2-oxindoles are selectively synthesized in good yields with excellent enantio- and regioselectivities.