Catalytic Enantioselective Tandem Carbonyl Ylide Formation/1,3-Dipolar Cycloaddition Reactions of α-Diazo Ketones with Aromatic Aldehydes using Dirhodium(II) Tetrakis[N-benzene-fused-phthaloyl-(S)-valinate]
example of the enantioselective intermolecular 1,3-dipolar cycloaddition of a chiral dirhodium(II) catalyst-associated carbonylylide with an aromatic aldehyde dipolarophile is described. The tandem carbonylylide formation/cycloadditionreactions of 1-diazo-5-aryl-2,5-pentanediones with aromatic aldehydes using dirhodium(II) tetrakis[N-benzene-fused-phthaloyl-(S)-valinate] as a catalyst provide exclusively