Zinc-Catalyzed Addition of A Formyl Anion toα-Hydroxy Enones

Significance

The authors have previously reported the utility of formaldehyde hydrazones as formyl anion and cyanide equivalents (Synlett 2000, 1228). In this report, the authors have developed a methodology for the conjugate addition of a formyl anion to α-hydroxy enones that overcomes difficulties observed in previous attempts. The products are obtained with good yields and high stereoselectivities. The usefulness of the methodology and the obtained products is demonstrated by short and efficient synthesis of β-cyano acids.