A short synthesis of (−)-(4 R,5 S)-sitophilure using the regio- and stereoselective reduction of 3-acyltetrahydrothiopyran-4-ones with baker's yeast

Abstract

Bakers' yeast reduction of 3-acyltetrahydrothiopyran-4-ones is regio- and enantioselective, yielding predominantly (3 R,4 S)-3-acyl-4- hydroxytetrahydrothiopyranes with high optical purity. This reduction method coupled with the Raney-nickel desulfurization provides a ready access to the rice and maize weevils aggregation pheromone, (−)-(4 R,5 S)-sitophilure, in high optical purity.