Sulfur-containing heterocycles. Communication 10. Synthesis of mixed anhydrides of sulfonic and carboxylic acids

A general method was developed for the preparation of previously unreported anhydrides ofβ-sulfinocarboxylic acids, namely, 1,2-oxathiolan-5-one-2-oxides and 2,1-benzoxathibl-3-one-1-oxide (XIV) by the action of disodium salts ofβ-oxysulfinylcarboxylic acids with oxalyl chloride.