Hydrochloric Acid → HCID 70382339, compound

Participants

Reaction Steps

To a mixture, cooled at 18° C., of 19 g (0.17 mole) of potassium tert-butoxide in 100 ml of dimethylsulfoxide, 13.2 g (0.046 mole) of 2-hydroxyethyl 3-oxo-1,2-benzoisothiazoline-2-acetate 1,1-dioxide prepared in Example 1 are slowly added. The mixture is stirred for 10 minutes at room temperature and then rapidly dropped into 700 ml of 10% hydrochloric acid while cooling externally to 0°-5° C. The precipitate is kept under stirring at this temperature for 1-2 hours, then it is collected and washed with methylene chloride to give, after drying, 8.8 g (yield 67%) of 2-hydroxyethyl 4-hydroxy-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide, m.p. 158°-159° C., Rf 0.57 (TLC as in Example 1).

Provenance & Evidence