反应详情

4 ml of a solution of diethylaluminum chloride (1M in hexane) is added dropwise at 0° C. to a solution of 0.519 g of 2,5-difluoroaniline in 10 ml of anhydrous dichloromethane. The reaction solution is stirred at room temperature for a further 20 minutes and subsequently cooled back to 0° C. A solution of 0.147 g of propiolactone in 8 ml of dichloromethane is added dropwise and the reaction mixture is stirred at room temperature over a further 2 hours. The reaction mixture is subsequently hydrolysed at 0° C. with 30 ml of 0.2M HCl and the phases are separated. The aqueous phase is re-extracted with 2×50 ml of dichloromethane and the combined organic phases are washed with 50 ml of water, dried over sodium sulphate and concentrated by evaporation. The title compound is obtained as a beige solid from the residue by means of flash chromatography (SiO2 60F). Rf=0.15 (1:1 EtOAc-heptane); Rt=2.62.

1. temperaturesubsequently cooled back to 0° C
2. stirringthe reaction mixture is stirred at room temperature over a further 2 hours
3. customthe phases are separated
4. extractionThe aqueous phase is re-extracted with 2×50 ml of dichloromethane
5. washthe combined organic phases are washed with 50 ml of water
6. dry with materialdried over sodium sulphate
7. concentrationconcentrated by evaporation