Synthesis of optically active heterocyclic compounds via deracemization of 1,2-diol monotosylate derivatives bearing a long aliphatic chain by a combination of enzymatic hydrolysis with Mitsunobu inversion

Abstract

Abstract We have succeeded in accomplishing the deracemization of (±)-2-acetoxydecyl and (±)-acetoxy-6-benzyloxyhexyl tosylates, which have a long substituent, via an enzyme-mediated enantioselective hydrolysis with a Mitsunobu inversion using polymer-supported triphenylphosphine to afford the corresponding (S)-enantiomer. Enantiomerically pure (S)- and (R)-γ-dodecalactones, a fruit flavor, were synthesized from (S)-2-acetoxydecyl tosylate as the mutual starting material. The poisonous alkaloid (S)-coniine was also synthesized using enantiomerically pure allyl amine as the key intermediate derived from (S)-acetoxy-6-benzyloxyhexyl tosylate.