反应详情

To 3-amino-4,4,4-trifluoro-2-butenoic acid ethyl ester (529 mL, 3.47 mol) was added acryloylchloride (600 mL, 6.95 mol) dropwise over a period of 15 min. The suspension was stirred at RT for 1 h. The temperature was slowly raised with stirring to 80° C. (HCl gas evolution) and maintained at 80° C. for 5 h. Stirring continued overnight at 40° C. The mixture was cooled, diluted with toluene (2 L) and n-heptane (2 L) to precipitate the product and stirred for another 15 min at room temperature. The product was isoloated by filtration, the filter cake was washed with toluene/n-heptane (1:2; 4×100 mL) and dried in vacuo at 40° C. for 5 h. This procedure yielded the title compound (286 g, 35%) as a white solid, MS (ISP) 236.1 (M−H)−. Concentration of the mother liquor and addition of toluene/n-heptane (1:10) yielded a second crop of 29.8 g.

1. temperatureThe temperature was slowly raised
2. temperaturemaintained at 80° C. for 5 h
3. stirringStirring
4. waitcontinued overnight at 40° C
5. temperatureThe mixture was cooled
6. customto precipitate the product
7. stirringstirred for another 15 min at room temperature
8. filtrationThe product was isoloated by filtration
9. washthe filter cake was washed with toluene/n-heptane (1:2; 4×100 mL)
10. customdried in vacuo at 40° C. for 5 h