Acetic Anhydride → N-(7-Oxo-4,5,6,7-tetrahydro-1,3-benzothiazol-2-yl)acetamide

Participants

Reaction Steps

To acetic anhydride (80 mL) was added at rt 2-amino-5,6-dihydro-4H-benzothiazol-7-one (10 g, 59.4 mmol) and the yellow suspension was heated to reflux. After 1.75 h stirring at this temperature, the RM was allowed to cool with stirring, and stirred overnight at rt. After further cooling with an ice/NaCl bath, the suspension was filtered. The solid was then refluxed twice with acetone (10 mL then 15 mL) and filtered. The resulting solid was dried under vacuum at 40° C. overnight to afford the title compound as a beige solid (HPLC: tR 3.47 min (Method A3), M−H=211.1), 1H-NMR in DMSO-d6 (600 MHz): 12.55 (s, br, 1H); 2.84 (t, 2H); 2.48 (t, 2H); 2.17 (s, 3H); 2.065 (qt, 2H)).

Provenance & Evidence