反应详情

温度

-78 °C

A solution of 5.4 g of 2,3,5,6-tetrafluoro-anisole in 80 ml of absolute THF is cooled to -78° C. and treated with 20.6 ml of 1.6M butyllithium in hexane within 15 min. After 20 min. 7.4 g of 4-bromo-N-methoxy-N-methylbenzamide (prepared from 4-bromo-benzoyl chloride and N,O-dimethylhydoxylamine.hydrochloride with N-methylmorpholine as the base) in 10 ml of THF are added dropwise and the mixture is stirred at -78° C. for 2 hrs. The reaction solution is poured into cold 10% potassium hydrogen sulphate solution/ethyl acetate and the organic phase is washed with water and 10% sodium chloride solution and dried. After crystallization from cyclohexane there are obtained 5.8 g of (4-bromo-phenyl)-(2,3,5,6-tetrafluoro-4-methoxy-phenyl)-methanone, m.p. 80-82° C.

1. additionare added dropwise
2. washthe organic phase is washed with water and 10% sodium chloride solution
3. customdried
4. customAfter crystallization from cyclohexane