Catalytic asymmetric synthesis of Japonilure and its enantiomer

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.