반응 #733136

반응 방정식

4-(5-hydroxy-3-trifluoromethyl-pyrazol-1-yl)-benzoic acid ethyl ester

difluorochloromethane

potassium carbonate

→

4-(5-difluoromethoxy-3-trifluoromethyl-pyrazol-1-yl)-benzoic acid ethyl ester

수율 95.2%

용매

DMF

반응 조건

후처리

1. 1
   workup.WAITat 100° C. for 12 hours
2. 2
   온도The mixture was cooled to −78° C.
3. 3
   기타the precipitate was removed by filtration
4. 4
   세척washed with DMF (3×1 mL)
5. 5
   workup.ADDITIONThe filtrate and washings were poured into cold water (200 mL)
6. 6
   기타The resulting suspension was transferred into a centrifuge tube
7. 7
   workup.WAITthe contents were centrifuged at room temperature for 10 minutes
8. 8
   여과filtered

실험 절차

A mixture of 4-(5-hydroxy-3-trifluoromethyl-pyrazol-1-yl)-benzoic acid ethyl ester (1 g, 3.3 mmol), difluorochloromethane (3 g, 34 mmol) and potassium carbonate (0.5 g, 3.6 mmol) in DMF (9 mL) was stirred in a sealed tube at −78° C. for 3 minutes and then at 100° C. for 12 hours. The mixture was cooled to −78° C. and the precipitate was removed by filtration and washed with DMF (3×1 mL). The filtrate and washings were poured into cold water (200 mL). The resulting suspension was transferred into a centrifuge tube and the contents were centrifuged at room temperature for 10 minutes and filtered to give 4-(5-difluoromethoxy-3-trifluoromethyl-pyrazol-1-yl)-benzoic acid ethyl ester (1.1 g, 94% yield) as a yellow solid.

출처