Synthesis of pheromones by stereoselective carbonyl olefination: A unitised construction principle

A route of synthesis for the preparation of unsaturated pheromones is presented. It permits the synthesis of monounsaturated and diunsaturated compounds, with varying position and configuration of double bonds, by stereoselective carbonyl olefination. The choice of appropriate ω-functional aldehydes and phosphoranes makes possible the synthesis of (Z)-alkenols and alkenyl acetates with the double bond in any position desired. Bifunctional synthones are used in stereoselective Wittig reactions for the preparation of diunsaturated sex attractants.