Enantioselective preparation of 2-substituted- 1,3-dithiane 1-oxides using modified sharpless sulphoxidation procedures
作者:Philip C. Bulman Page、Robin D. Wilkes、Emest S. Namwindwa、Michael J. Witty
DOI:10.1016/0040-4020(95)01029-7
日期:1996.2
carried out using modified Sharpless conditions to furnish the corresponding sulphoxides in optically enriched form. Deacylation of 2-acyl-1,3-dithiane 1-oxide derivatives allows the preparation of 2-alkyl-1,3-dithiane 1-oxides and the parent 1,3-dithiane 1-oxide itself in high enantiomeric excesses.
Catalytic Asymmetric Oxidation of Cyclic Dithioacetals: Highly Diastereo- and Enantioselective Synthesis of the <i>S</i>-Oxides by a Chiral Aluminum(salalen) Complex
The reaction of nonsubstituted 1,3-dithiane also proceeded in a highlyenantioselective manner to give the monoxide with a small formation of the trans-1,3-dioxide, an overoxidation product. Five-membered 1,3-dithiolanes and seven-membered 1,3-dithiepanes also underwent oxidation to give monoxides with high diastereo- and enantioselectivity. It was found that the equilibrium between the two chairlike
Stereoselective enzyme-catalysed oxidation–reduction reactions of thioacetals–thioacetal sulphoxides by fungi
作者:Barbara J. Auret、Derek R. Boyd、Fiona Breen、Ruth M. E. Greene、Peter M. Robinson
DOI:10.1039/p19810000930
日期:——
bis-(p-tolythio)methane to form the corresponding monosulphoxides occurred in the presence of growing cultures of Aspergillus foetidus and a Helminthosporium species. The degree and preferred direction of stereoselectivity occurring during the asymmetric oxidation and reduction steps was deduced from the enantiomeric excess (e.e.) and absolute stereochemistry of the isolated 1,3-dithian 1-oxide and p-tolythio-(