反应详情

A 250-mL round bottomed flask was charged with N-hydroxy-2-(4-nitrophenyl)acetamidine (1 g, 5 mmol, 1 eq.), methyl propiolate (500 mg, 6 mmol, 1.2 eq.) and EtOH (24 ml). The resulting mixture was stirred under reflux for 7 hrs. After cooling to room temperature, the volatile material was removed under reduced pressure and the residue was added phenyl ether (200 ml). The mixture was stirred at 190° C. for 30 minutes. After cooling to room temperature, the mixture was poured into hexane (1 L). Solid was collected and washed with hexane. The crude product thus obtained (964 mg) was purified by chromatography on silica gel using 10˜20% acetone in dichloromethane as eluent to afford the title compound as a gray solid (220 mg, 17% yield over two steps).

1. temperatureunder reflux for 7 hrs
2. customthe volatile material was removed under reduced pressure
3. additionthe residue was added phenyl ether (200 ml)
4. stirringThe mixture was stirred at 190° C. for 30 minutes
5. temperatureAfter cooling to room temperature
6. additionthe mixture was poured into hexane (1 L)
7. customSolid was collected
8. washwashed with hexane
9. customThe crude product thus obtained (964 mg)
10. customwas purified by chromatography on silica gel using 10˜20% acetone in dichloromethane as eluent