反应详情

76.0 g of ethyl 3-cyano-2,4-dichloro-5-fluorobenzoylacetate (0.25 mol), 66.6 g of triethyl orthoformate (0.45 mol) and 77.4 g of diacetyl oxide (0.72 mol) were stirred at 150° C. for 2.5 hours. Fractions having a lower boiling point were evaporated under reduced pressure. To the residue was added 250 ml of anhydrous ethanol. 14.5 g of cyclopropylamine (0.25 mol) was added to the solution and the reaction was then carried out for 2 hours. The resulting mixture was filtered under suction. The residue was recrystallized from a mixture of petroleum ether and cyclohexane to yield 65.0 g (0.175 mol) of ethyl 2-(3-cyano-2,4-dichloro-5-fluorobenzoyl)-3-cyclopropylaminoacrylate in 70.1% yield.

1. customwere evaporated under reduced pressure
2. additionTo the residue was added 250 ml of anhydrous ethanol
3. filtrationThe resulting mixture was filtered under suction
4. customThe residue was recrystallized from a mixture of petroleum ether and cyclohexane