反应详情

温度

95 °C

27.6 g of finely-pulverulent potassium carbonate, 18.2 g of ethyl 2-chloroethylcarbamate and 1 g of powdered potassium iodide are added to a solution of 22.2 g of 4-(3,5-difluorophenoxy)phenol in 80 ml of dimethylformamide. The reaction mixture is heated for 16 hours at 95° C., with stirring. After this, the reaction mixture is filtered, the filtrate is poured into 400 ml of water, and the mixture is extracted repeatedly with diethyl ether. The combined organic phases are washed with water and dried over sodium sulfate, and the solvent is distilled off. The residue is purified by chromatography over silica gel (eluent: n-hexane/diethyl ether 3:1), which gives the pure ethyl 2-[4-(3,5-difluorophenoxy)phenoxy]ethylcarbamate as a colourless compound which soon crystallizes and has a melting point of 54°-56° C. The 1H-NMR spectrum agrees with the indicated structure.

1. filtrationAfter this, the reaction mixture is filtered
2. additionthe filtrate is poured into 400 ml of water
3. extractionthe mixture is extracted repeatedly with diethyl ether
4. washThe combined organic phases are washed with water
5. dry with materialdried over sodium sulfate
6. distillationthe solvent is distilled off
7. customThe residue is purified by chromatography over silica gel (eluent: n-hexane/diethyl ether 3:1), which