反应详情

To a solution of 2-bromo-4,5-difluoroaniline (100 g) and dimethyl sulfide (49 ml) in anhydrous dichloromethane (1.2 liter) is added gradually N-chlorosuccinimide (90 g) at below 15° C., and thereafter is further added in portions triethylamine (93 ml) at 15° C. After the addition, the mixture is refluxed for 7 hours. After cooling, 10% aqueous sodium hydroxide (one liter) is added to the reaction mixture, and the mixture is extracted with dichloromethane. The extract is dried over magnesium sulfate and concentrated, and the resulting residue is purified by silica gel column chromatography (solvent, dichloromethane:n-hexane=1:2). The product is recrystallized from n-hexane to give 6-bromo-3,4-difluoro-2-methylthiomethylaniline (52 g) as a white crystal, m.p. 60°-61° C.

1. additionAfter the addition
2. temperaturethe mixture is refluxed for 7 hours
3. temperatureAfter cooling
4. extractionthe mixture is extracted with dichloromethane
5. dry with materialThe extract is dried over magnesium sulfate
6. concentrationconcentrated
7. customthe resulting residue is purified by silica gel column chromatography (solvent, dichloromethane:n-hexane=1:2)
8. customThe product is recrystallized from n-hexane