A concise, protection-free and divergent approach for the enantioselective syntheses of two pheromonal epoxide components of the fall webworm moth and other species.

On the basis of Zhou's modified Sharpless asymmetric epoxidation, sequential coupling reactions, and a divergent strategy, the protection-free syntheses of two main pheromonal components 1 and 5, found in the fall webworm moth, Hyphantria cunea, and other species have been accomplished in 10 steps (for two compounds). The overall yields are 31% for 1, 28% for 5, and 25% for both 1 and 5, respectively. The ee values of the final products 1 and 5 are at least 99%.