反应详情

Sodium hydride (60% dispersion, 150 mg, 3.8 mmol) was added to a solution of 4-chloro-N-methylbenzenesulfonamide (640 mg, 3.1 mmol) in DMF (12 ml) while cooling in an ice/water bath. After stirring for 15 min the mixture was allowed to warm to room temperature and stirred for a further 30 min. Methyl 4-bromomethyl-3-chlorothiophene-2-carboxylate (1.08 g, 4.0 mmol) was added and the mixture was stirred for 18 h. 0.3N Potassium hydrogen sulphate solution was added and the mixture evaporated. The mixture was extracted with ethyl acetate and the organic extract was washed with brine, dried and reduced. Chromatography (25% EtOAc/75% 60-80 pet ether) yielded methyl 3-chloro(N-(4-chlorobenzenesulphonyl)-N-methylaminomethyl)thiophene-2-carboxylate (1.25 g, 79%) as a white solid.

1. temperaturewhile cooling in an ice/water bath
2. stirringstirred for a further 30 min
3. stirringthe mixture was stirred for 18 h
4. customthe mixture evaporated
5. extractionThe mixture was extracted with ethyl acetate
6. extractionthe organic extract
7. washwas washed with brine
8. customdried