反应详情

A solution of 3.55 g of 2-chloro-2-(4-chloro-3-chloroformylphenyl)-5-trifluoromethylpyridine in 10 ml of methylene chloride was added dropwise to a mixture of 3.63 g of L-valine ethyl ester hydrochloride, 7.9 g of pyridine and 30 ml of methylene chloride at 23° C. After stirring for 60 hours, 160 ml of methylene chloride were added. The mixture was washed three times with 150 ml of water each time, dried over sodium sulfate and then concentrated. The crude product was purified by chromatography on silica gel with cyclohexane/ethyl acetate (10:1). Yield: 2.2 g (48%) of colorless crystals; melting point: 90°-92° C.

1. washThe mixture was washed three times with 150 ml of water each time
2. dry with materialdried over sodium sulfate
3. concentrationconcentrated
4. customThe crude product was purified by chromatography on silica gel with cyclohexane/ethyl acetate (10:1)