The enantioselective synthesis of α-benzyloxy aldehydes containing a terminal alkene was carried out from chiral pool l-(+)-tartaric acid by employing the stereoselective reduction of a 1,4-diketone as the key step. The synthetic utility of these aldehydes was demonstrated in the synthesis of pine beetle pheromones (+)-exo-brevicomin, (+)-iso-exo-brevicomin and a formal synthesis of 2,7-cis-disubstituted oxepane (−)-isolaurepan.