反应详情

温度

80 °C

To 28.7 ml of anhydrous N,N-dimethylformamide at 0° C. were added slowly 80.7 ml of phosphorus oxychloride then 15.6 g of 2-ethyl-5-methyl-2H-pyrazol-3-ol. The mixture was stirred under nitrogen at 80° C. for 1 hour, poured into 700 ml of water at 0° C. then extracted six times with 350 ml of diethyl ether. The combined extracts were dried over magnesium sulphate, filtered and evaporated to leave 9.3 g of 5-chloro-1-ethyl-3-methyl-1H-pyrazole-4-carbaldehyde as an orange liquid which was used without further purification.

1. extractionthen extracted six times with 350 ml of diethyl ether
2. dry with materialThe combined extracts were dried over magnesium sulphate
3. filtrationfiltered
4. customevaporated