A Concise Asymmetric Synthesis of (2<i>S</i>,3<i>S</i>,7<i>S</i>)-3,7-Dimethylpentadecan-2-yl Acetate and Propionate, the Sex Pheromones of Pine Sawflies
7S)-3,7-Dimethylpentadecan-2-yl acetate (2) and its propionate analogue (3) are the main sex pheromones of all Neodiprion species and Diprion similes, respectively. Starting from (S)-malic acid and employing a highly chemo-, regio-, and stereoselective tandem ester reduction−epoxide formation−reductive epoxide-opening reaction protocol, an efficient total synthesis of (2S,3S,7S)-2 and -3 is reported