反应详情

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

1. temperaturewhile cooling with ice
2. customWhen the exothermic reaction
3. stirringthe mixture is stirred for a further hour at room temperature
4. customthe residue is recrystallised from cyclohexane/petroleum ether