反应详情

Aqueous sodium hydroxide (1M, 145 ml, 145 mmol) was added to a suspension of 6,7-dichloro-5-di(methanesulphonyl)amino-2,3-dimethoxyquinoxaline (from step (a), 12.28 g, 28.6 mmol) and the mixture was stirred at room temperature for 16 hours. The resulting orange solution was treated with 2M hydrochloric acid (to pH3) and the solid which precipitated was filtered off, washed with water and ether, and dried in vacuo at 80° C. to give N-(6,7-dichloro-2,3-dimethoxyquinoxalin-5-yl)methanesulphonamide (8.46 g, 84%) as a white solid, m.p. 225°-227° C.

1. customthe solid which precipitated
2. filtrationwas filtered off
3. washwashed with water and ether
4. customdried in vacuo at 80° C.