Diastereo‐ and Enantioselective Aldol Reactions via α‐Silyl Ketones, Asymmetric Synthesis of the Aggregation Pheromone Sitophilure

The β-hydroxy ketones syn-2 are accessible in good yields and with high diasteromeric and enantiomeric purity by asymmetric Aldol reaction via the chiral methylene components (R)-1. This makes possible, for example, an efficient synthesis of both enantiomers of sitophilure (RC2H5), the aggregation pheromone of rice and maize weevils, which cause great damage to stored grain.