A Concise Approach to Oxo-Dehydrorotenoid by Direct Lactonization and the Total Syntheses of Stemonone, Rotenonone, 6-Oxo-dehydroelliptone, and 6-Oxo-6a,12adehydrodeguelin

摘要

An approach to construct the oxo-dehydrorotenoids via direct lactonization of isoflavone-2-carboxylic acids is reported. The present reaction proceeds smoothly with good substrate scope and an operationally simple protocol. The application of this method for the total syntheses of the natural products, stemonone, 6-oxo-dehydroelliptone, rotenonone, and 6-oxo-6a,12a-dehydrodeguelin, are demonstrated.