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