Catalytic asymmetric synthesis of Japonilure and its enantiomer
Abstract A mild, concise, and highly enantioselective (93% ee) synthesis of Japonilure and its enantiomer, Anomala osakana pheromone, is described. The key steps involve the asymmetric addition of methyl propionate to undec 2 ynal with a Zn ProPhenol catalyst and the selective and partial reduction of the diynol ester to the cis enol ester with Brown's P2 Ni catalyst, providing the first synthesis of the enol ester via semi hydrogenating diynol ester.