Hydrochloric Acid → 6-Chloro-3-methyl-5-nitro-1,2-benzisothiazole

Participants

Reaction Conditions

Reaction Steps

A mixture of tert-butyl nitrite (3.30 mL, 0.0278 mol) and copper(II) chloride (2.98 g, 0.0222 mol) in acetonitrile is heated to 65° C., treated portionwise with 6-amino-3-methyl-5-nitro-1,2-benzisothiazole (3.88 g, 0.0185 mol), stirred at 65° C., cooled to room temperature, and poured into 20% hydrochloric acid. The resultant aqueous mixture is extracted with ethyl acetate. The organic extracts are combined, washed with 20% hydrochloric acid, dried over anhydrous magnesium sulfate, and concentrated in vacuo to obtain a solid. Flash column chromatography of the solid using silica gel and methylene chloride/hexanes solutions (1:1 and 3:1) gives the title product as a pale, yellow solid (2.54 g, mp 156-158° C.) which is identified by NMR spectral analyses.

Provenance & Evidence