反应详情

温度

73.5 °C

7.1 kg of the product of the formula (II) were suspended in 171.6 kg of ethyl acetate and 42 kg of ethanol, and the mixture was stirred at reflux (internal temperature about 73-74° C.) for 20 h. The suspension was cooled to RT and filtered off with suction, and the product was washed four times with in each case 12.2 kg of ethyl acetate. The product was then washed twice with in each case 12.2 kg of water to expel the ethyl acetate, and the moist product was dried under reduced pressure at 50° C. until its mass remained constant. The yield of pure product of the formula (I) was 4.3 kg or 84% of theory. The content of the product was more than 99% (HPLC).

1. temperatureThe suspension was cooled to RT
2. filtrationfiltered off with suction
3. washthe product was washed four times with in each case 12.2 kg of ethyl acetate
4. washThe product was then washed twice with in each case 12.2 kg of water
5. customthe moist product was dried under reduced pressure at 50° C. until its mass