STUDIES OF THE SYNTHESIS OF 2-HYDROXY-6-METHYL-1 AND 2-ACETOXY-6-METHYL-1,4-OXATHIANE S-OXIDES AND RELATED-COMPOUNDS

The 4B.-and 4-oxides of (2B., 6) and (2, 6) -2-acetoxy-6-methyl-l, 4-oxathiane have been prepared by routes involving oxidation of the res­pective 1,4-oxathianes with periodate. In these compounds, an equatorial acetoxy group at C-2 leads to preponderant axial oxygenation by periodate, whereas an axial acetoxyl group at C-2 favours equatorial -oxygenation. Basic hydrolysis of (2B., 4, 6)-2-acetoxy-6-methyl-l,4-oxahiane -oxide provides a convenient route to (4, 6)-2-hydroxy-6-methyl-l,4-oxathiane ­oxide. The allyl ( and prop-l-enyl) and .e--nitrophenyl groups were shown to be unsuitable for the protection of HO-2 during the synthesis of 2-hydroxy­1,4-oxathiane derivatives.

J W WEBBER ,M H QADIR ,