反应详情

温度

150 °C

A mixture of 2-amino-5,6-dihydro-4H-benzothiazol-7-one (0.5 g, 3 mmol) and N,N-dimethylformamide dimethyl acetal (1.96 mL, 1.76 g, 14.8 mmol) in EtOH (2 mL) was heated under microwave irradiation (300 W, 150° C.) for 30 min. The mixture was concentrated under vacuum before purification by flash column chromatography (50% EtOAc:hexane) to afford the title product as a tan solid (0.49 g, 59%): mp 185-186° C. Anal. RP-HPLC: tR 9.3 min (0-60% MeCN, purity 100%). 1H-NMR (CDCl3): δ 8.23 (s, 1H, CH), 7.44 (s, 1H, CH), 3.13 (s, 3H, CH3), 3.11 (s, 3H, CH3), 3.08 (s, 6H, N(CH3)2), 3.00 (t, 2H, J 6.6, CH2), 2.83 (t, 2H, J 6.6, CH2). MS (ESI+): m/z 279.15 (M+H)+.

1. concentrationThe mixture was concentrated under vacuum before purification by flash column chromatography (50% EtOAc:hexane)