反应详情

A stirred solution of 9.7 g (0.050 mole) of 2-chloro-5-methoxyaniline hydrochloride in 120 mL of acetic acid was cooled to 15° C. To this cold mixture was added 4.0 g (0.025 mole) of bromine. After complete addition, the mixture was allowed to warm to room temperature and was stirred for approximately 18 hours. The mixture was poured into ice water. To the resultant mixture was added a solution of 2.0 g (0.05 mole) of sodium hydroxide in 10 mL of water. This mixture was extracted with 200 mL of diethyl ether. The ether extract was dried over anhydrous magnesium sulfate, filtered, and the filtrate evaporated under reduced pressure to leave an oil. The oil was purified by column chromatography on silica gel, eluting with methylene chloride, to yield 7.3 g of 4-bromo-2-chloro-5-methoxyaniline as a solid, mp 40°-41° C.

1. additionAfter complete addition
2. extractionThis mixture was extracted with 200 mL of diethyl ether
3. extractionThe ether extract
4. dry with materialwas dried over anhydrous magnesium sulfate
5. filtrationfiltered
6. customthe filtrate evaporated under reduced pressure
7. customto leave an oil
8. customThe oil was purified by column chromatography on silica gel
9. washeluting with methylene chloride