反应详情

A mixture of 5-bromo-2-(2-chlorophenylamino)-3,4-difluorobenzoic acid methyl ester (2.07 g, 5.50 mmol), NCS (789 mg, 5.91 mmol), and catalytic amount of conc. HCl in DMF (41 mL) was stirred for 1 hour at room temperature. The reaction mixture was diluted with EtOAc, and washed with water (5×). The organic layer was dried over MgSO4, filtered, and concentrated to give the crude material which was purified by silica gel flash column chromatography (3 to 5% EtOAc in hexanes) to afford the desired product (2.02 g, 89%).

1. washwashed with water (5×)
2. dry with materialThe organic layer was dried over MgSO4
3. filtrationfiltered
4. concentrationconcentrated
5. customto give the crude material which
6. customwas purified by silica gel flash column chromatography (3 to 5% EtOAc in hexanes)