反应详情

To a solution of 4-(2,2,2-trifluoroethyl)piperazine-1-amine (4.72 g, 25.8 mmol) in ethanol (43 mL), ethyl 2-ethoxy-4-oxo-4,5-dihydrofuran-3-carboxylate (4.70 g, 23.5 mmol) which similarly prepared according to the procedure described in the Example 74, Third step was added at ambient temperature. The mixture was stirred for 2 h. The precipitate was collected by filtration, washed with diethyl ether and hexane then dried to afford ethyl 4-oxo-2-{[4-(2,2,2-trifluoroethyl)piperazinyl]amino}-4,5-dihydrofuran-3-carboxylate as solid (5.64 g, y. 71%).

1. additionwas added at ambient temperature
2. filtrationThe precipitate was collected by filtration
3. washwashed with diethyl ether and hexane
4. customthen dried