Asymmetric Intramolecular C-H Insertion Promoted by Dirhodium(II) Carboxylate Catalyst Bearing Axially Chiral Amino Acid Derivatives

A dirhodium(II) carboxylate catalyst bearing axially chiral amino acid derivatives is prepared. X-ray crystal structure analysis reveals that four of the bridging ligands are aligned in a C-2-symmetry-like conformation. This catalyst is effective in the asymmetric intramolecular C-H insertion of alpha-aryl-alpha-diazoacetates to alpha-aryl-beta-substituted gamma-lactones with a reasonable level of diastereo-and enantioselectivity, especially in the reaction of phenyl-and beta-naphthyl-substituted substrates.