反应详情

温度

20 °C

At 20° C., 150 g of 2-dichloromethyl-8-trifluoromethyl-4H-3,1-benzoxazine-4-one, 120 g of ethyl 3-(2-thiazolylamino)-3-oxo-propanoate and 1.5 liters of tetrahydrofuran were mixed together and stirred for 30 minutes and then, while maintaining the temperature at 20° C., 40 g of sodium hydroxide in flakes were added thereto. After stirring the mixture at 20° C. for two hours, it was poured into a mixture of 4.5 liters of water and 150 ml of concentrated hydrochloric acid and the mixture was stirred at 0° to +5° C. for 30 minutes. The crystals formed were separated, rinsed with water and dried to obtain 255 g of ethyl 2-[(2,2-dichloro-1-oxoethyl)-amino]-β-oxo-α-[(2-thiazolylamino)-carbonyl]-3-(trifluoromethyl)-benzene-propanoate melting at 90° C.

1. stirringAfter stirring the mixture at 20° C. for two hours
2. stirringthe mixture was stirred at 0° to +5° C. for 30 minutes
3. customThe crystals formed
4. customwere separated
5. washrinsed with water
6. customdried