Asymmetric Michael Addition of β-Ketoesters to Enones Catalyzed by the Lithium Salt of a Primary β-Amino Acid

A highly enantioselective Michael addition of β-ketoesters to enones was achieved by using the salt of a readily available primary β-amino acid as the catalyst. The obtained Michael adducts were converted into enantioenriched 1,5-diketones in high yields through a common decarboxylation reaction under acidic conditions. A plausible reaction mechanism for the Michael addition reaction, which is supported by results of mechanistic studies that include DFT calculations, is also described.