反应详情

温度

90 °C

9 g of 3-(2,4-dichlorophenyl)-5-hydroxy-1-methyl-1H-pyrazole from Example 4.1 were initially charged in 50 ml of dimethylacetamide, and 5.4 g of potassium carbonate were added. The mixture was heated at 90° C., and 48 g of gaseous chlorodifluoromethane were introduced over a period of 1 h. The mixture was poured into 800 ml of water and extracted twice with 300 ml of MTBE, and the combined organic phases were extracted once with 100 ml of water and once with 100 ml of saturated sodium chloride solution. Drying and concentration of the organic phase gave 10.2 g of 3-(2,4-dichlorophenyl)-5-difluoromethoxy-1-methyl-1H-pyrazole of a purity of 56% (yield 50.2%, based on the title compound), which was purified further by vacuum distillation.

1. extractionextracted twice with 300 ml of MTBE
2. extractionthe combined organic phases were extracted once with 100 ml of water and once with 100 ml of saturated sodium chloride solution
3. customDrying