Formal Synthesis of (-)-Frontalin through Diastereoselective Hydrocyanation of a β-Keto Sulfoxide

Abstract

The diastereoselective synthesis of (S)-4-(2,2,4-trimethyl-1,3-dioxolan-4-yl)butan-1-ol (9), an intermediate in the asymmetric synthesis of the pine beetle pheromone (-)-frontalin [(1S,5R)-1,5-dimethyl-6,8-dioxabicyclo[3.2.1]octane] (1), has been accomplished starting from the β-keto sulfoxide 2, derived from glutaric anhydride. The key step of the synthetic sequence is the diastereoselective hydrocyanation of 2 by diethylaluminum cyanide.