Water → 4H-1,4-Benzothiazin-3-one

Participants

Reaction Steps

A solution of bromo acetylbromide in toluene (20 ml) was added dropwise to an ice-cooled stirred solution of o-mercaptoaniline (10 mmol, 2.5 g) in a mixture of pyridine and toluene (50 ml, 30 ml). The mixture was allowed to heat to room temperature and stirring was continued for 2 hours followed by reflux for 30 min., whereafter water (100 ml) was added. The organic phase was separated, dried (MgSO4) and evaporated to give 3,4-dihydro-3-oxo-2H-1,4-benzothiazine. M.p. 170°-171° C.

Provenance & Evidence