A convenient route to 3-substituted isothiazoles using nitrile sulfide cycloaddition chemistry

Abstract

Isothiazole-3- and 4-carboxylate esters are readily prepared by 1,3-dipolar cycloaddition of nitrile sulfides, generated by thermal decarboxylation of the corresponding 1,3,4-oxathiazol-2-ones, to acrylate, fumarate and maleate esters, followed by phase-transfer-mediated hypochlorite oxidation of the resulting 2-isothiazoline cycloadducts.