反应详情

n-Propylamine (36.7 ml, 26.33 g, 444 mmol) was added to a solution of crude 2,6-difluoro-N-formyl-N-vinyl-benzamide from step a (47 g, 222 mmol) in dichloromethane (200 ml). There was a weak exotherm. The reaction mixture was kept at room temperature with a cold water bath. The solution was then concentrated on the rotovap to give a brown oil, which was crystallised from ethanol/water to yield 30 g (75%) of pure 2,6-difluoro-N-vinyl-benzamide as beige crystals. A further 5.7 g was crystallised from concentration of the mother liquors. M.p. 103-107° C.

1. customThe reaction mixture was kept at room temperature with a cold water bath
2. concentrationThe solution was then concentrated on the rotovap
3. customto give a brown oil, which
4. customwas crystallised from ethanol/water