反应详情

4.3 g of cyclopropylamine are added dropwise, with cooling in ice and stirring, to a solution of 24.9 g of ethyl 2-(2,4-dichloro-5-fluorobenzoyl)-3-ethoxyacrylate (5) in 80 ml of ethanol. When the exothermic reaction has moderated, the mixture is stirred at room temperature for a further 1 hour, the solvent is removed in vacuo and the residue is recrystallised from cyclohexane/petroleum ether. 22.9 g of ethyl 2-(2,4-dichloro-5-fluorobenzoyl)-3-cyclopropylaminoacrylate (6) of melting point 89°-90° C. are obtained.

1. temperaturewith cooling in ice
2. customWhen the exothermic reaction
3. customthe solvent is removed in vacuo
4. customthe residue is recrystallised from cyclohexane/petroleum ether