反应详情

To a solution of 3-methoxy-4-bromoisothiazole (2.9 g, 15 mmol) in methylene chloride (15 ml) there can be was added, in portions, 3,5-dinitroperbenzoic acid (3.4 g, 15 mmol) with ice bath cooling. After about one hour, the precipitated 3,5-dinitrobenzoic acid can be filtered off and the solvent evaporated in vacuo. By triturating the residue with diethyl ether, a crystalline product, 3-methoxy-4-bromoisothiazole-1-oxide, can be obtained. Additional material can be obtained by chromatographing the mother liquors on silica gel, eluting with chloroform.

1. temperaturecooling
2. filtrationthe precipitated 3,5-dinitrobenzoic acid can be filtered off
3. customthe solvent evaporated in vacuo
4. customBy triturating the residue with diethyl ether