反应详情

2,6-difluorobenzoyl chloride (35.4 ml, 50 g, 284 mmol) was added dropwise with stirring to a solution of N-vinylformamide (18 ml, 18.3 g, 258 mmol), 4-dimethylaminopyridine (3.1 g, 25.8 mmol), and triethylamine (53.8 ml, 39 g, 387 mmol) in dichloromethane (200 ml). The temperature was kept at ca 20° C. with an ice/water bath. After the addition the mixture was stirred two hours at room temperature then shaken between tBuOMe and water. The organic phase was washed with half saturated brine, dried with Na2SO4 and evaporated to give 47 g (87% crude) of 2,6-difluoro-N-formyl-N-vinyl-benzamide, which contained ca 60% of 2,6-difluoro-N-vinyl-benzamide, which is the product of the next step, in which the formyl group has already been cleaved.

1. customThe temperature was kept at ca 20° C. with an ice/water bath
2. additionAfter the addition the mixture
3. washThe organic phase was washed with half saturated brine
4. dry with materialdried with Na2SO4
5. customevaporated