反应详情

To a stirring solution of 3-tert-butyl-1-(3-fluorophenyl)-1H-pyrazole-5-carboxylic acid (0.26 g, 0.60 mmol) and TEA (0.13 ml, 0.90 mmol) in 1,4-dioxane (9 ml) was added DPPA (0.16 ml, 0.75 mmol), After stirring for 30 min at RT, 2,2,2-trichloroethanol (0.58 ml, 6.0 mmol) was added and the reaction was heated at 100° C. for 2 h. The reaction mixture was diluted with brine (10 ml) and extracted with EtOAc (3×20 ml). The combined organic phases were washed with 5% citric acid (10 ml), satd. NaHCO3 (10 ml), dried (MgSO4), filtered and evaporated. The crude product was purified by chromatography to afforded 2,2,2-trichloroethyl 3-tert-butyl-1-(3-fluorophenyl)-1H-pyrazol-5-ylcarbamate (0.180 g, 73% yield) as colorless oil. MS (ESI) m/z: 410(M+H+).

1. temperaturethe reaction was heated at 100° C. for 2 h
2. extractionextracted with EtOAc (3×20 ml)
3. washThe combined organic phases were washed with 5% citric acid (10 ml)
4. dry with materialNaHCO3 (10 ml), dried (MgSO4)
5. filtrationfiltered
6. customevaporated
7. customThe crude product was purified by chromatography