Stereoselective chemo-enzymatic approaches to the synthesis of C2 1,3-dithiane-1,3-dioxide

Two enzyme-mediated methods are presented for the preparation of enantiomerically enriched C2 1,3-dithiane-1,3-dioxide. The first takes advantage of a trans stereoselective oxidation by NaIO4 of enantiomerically pure (R) 1,3-dithiane-1-oxide obtained by cyclohexanone monooxygenase. In the second method, a kinetic resolution consisting of a domino hydrolysis-decarboxylation process of (±) 2-carbethoxy-1,3-dithiane- trans-1,3-dioxide is described. The target molecule is obtained with enantiomeric excesses up to 90%.