反应详情

温度

10 °C

10.4 g (0.1575 mole) of 85% potassium hydroxide are dissolved in 75 ml of water. 3.5 g (0.0825 mole) of cyanamide are added at 20° C. and the clear, colourless solution is cooled to 10° C. Then a solution of 25.8 g (0.075 mole) of 2-[4-(4-trifluoromethylphenoxy)phenoxy]propionyl chloride in 15 ml of acetone is added dropwise such that the temperature does not exceed 15° C. After the reaction mixture has been stirred for 45 minutes at this temperature, 9 g (0.09 mole) of 37% aqueous hydrochloric acid are added dropwise at 5° C. The product precipitates as an oil which crystallises on standing over 30 minutes. The colourless crystals are isolated by filtration, washed with water, dried over phosphorous pentoxide, affording 24.9 g (95.0% of theory) of 2-[4-(4-trifluoromethylphenoxy)phenoxy]propionic acid N-cyanamide with a melting point of 125°-127° C.

1. customdoes not exceed 15° C
2. additionare added dropwise at 5° C
3. customThe product precipitates as an oil which
4. customcrystallises
5. customThe colourless crystals are isolated by filtration
6. washwashed with water
7. dry with materialdried over phosphorous pentoxide