The synthesis of the optically active nitroolefin 6 commenced with desymmetrization of meso-1,3-diol 7 (Scheme [²] ). Lipase PS-mediated acetylation at -15 ˚C afforded the optically active monoacetate, [8] which was immediately converted into BocNs-imide 8 [9] (95% ee) under the Mitsunobu conditions [¹0] to prevent racemization of the diol monoacetate. After removal of the Boc group, ozonolysis of the terminal olefin 9, followed by dehydration of the resulting ...