反应详情

15.8 g of 3,5-dichloro-2-acetylpyridine are introduced together with 12.0 ml of trifluoroethyl acetate into 125 ml of absolute ether. With stirring, the mixture is cooled using an ice-bath and 46.6 ml of, a 21% sodium ethanolate solution in ethanol are added dropwise. The ice-bath is then removed and the mixture is subsequently stirred overnight at 25° C. After cooling the reaction mixture in an ice-bath and adding dropwise 7.5 ml of glacial acetic acid, the mixture is concentrated in vacuo. 39.0 g of 1-(3,5-dichloro-2-pyridyl)-3-trifluoromethylpropane-1,3-dione are obtained, which can be used directly for the following cyclisation step.

1. temperaturethe mixture is cooled
2. customThe ice-bath is then removed
3. temperatureAfter cooling the reaction mixture in an ice-bath
4. additionadding dropwise 7.5 ml of glacial acetic acid
5. concentrationthe mixture is concentrated in vacuo