Enantioselective synthesis of (R)- and (S)-2-methyl-4-octanol, the male-produced aggregation pheromone of Curculionidae species

This work describes an enantioselective synthesis of (R)- and (S)-2-methyl-4-octanol, a compound that has been identified as the aggregation pheromone of some sugarcane weevils. (S)-2-Methyl-4-octanol was efficiently prepared in five steps and 20% overall yield, and its (R)-enantiomer, in six steps and 14% overall yield, both from commercial isovaleryl chloride. The key step of our synthetic route is the asymmetric reduction of ethyl 5-methyl-3-oxohexanoate with Saccharomyces cerevisiae to its corresponding (S)-alcohol in good yield and high enantiomeric excess. (C) 2002 Elsevier Science Ltd. All rights reserved.