Catalytic Enantioselective Total Syntheses of Bakkenolides I J and S: Application of a Carbene-Catalyzed Desymmetrization

摘要

A general strategy for the catalytic asymmetric syntheses of the bakkenolides is reported. The key bond-forming step involves an N-heterocyclic carbene catalyzed desymmetrization of a 1,3-diketone to form three new bonds in one step with excellent enantio– and diastereoselectivity. This intramolecular reaction allows direct access to the hydrindane core of the bakkenolides family and enables a facile synthesis of these natural products.