Syntheses a l'aide de sulfones (xxxvii): Synthese de trois pheromones a une double liaison z : z, 8-dda ; z, 9-dda ; z. 9-tda

The title compounds Z,8-dodecen-1yl acetate, Z,9-dodecen-1yl acetate and Z,9-tetradecen-1yl-acetate) have been synthesized in three efficient steps : the reaction mixture from metalated w-hydroxy sulfones and appropriate aldehydes was quenched with acetic anhydride yielding a diastereoisomeric mixture of β-acetoxy sulfones. Convergent elimination with powdered sodium hydroxide led to the E vinylic sulfone. Stereospecific hydrogenolysis of the sulfonyl group was carried out with sodium dithionite leading to the unsaturated alcohol (99% Z).