Реакция #41171

Уравнение реакции

Cyclohexyl-hydrazine hydrochloride

2-dimethylaminomethylene-4,4,4-trifluoro-3-oxo-butyric acid ethyl ester

sodium acetate

→

1-cyclohexyl-5-trifluoromethyl-1H-pyrazole-4-carboxylic acid ethyl ester

Выход 58.5%

Растворители

ethanol

Условия реакции

Обработка

1. 1
   ТемператураAfter cooling to room temperature
2. 2
   Другоеthe reaction mixture was partitioned between methylene chloride and water
3. 3
   ПромывкаThe organic phase was washed with water and brine
4. 4
   ЭкстракцияEach aqueous phase was back extracted with a second portion of methylene chloride
5. 5
   Сушкаdried over sodium sulfate
6. 6
   Концентрированиеconcentrated in vacuo
7. 7
   ДругоеPurification by flash chromatography
8. 8
   Промывкаeluting with a 5-40% ethyl acetate-hexanes

Методика

Cyclohexyl-hydrazine hydrochloride (0.276 g, 1.59 mmol, CAS #24214-73-1, purchased from Aldrich), 2-dimethylaminomethylene-4,4,4-trifluoro-3-oxo-butyric acid ethyl ester (0.459 g, 1.67 mmol) and anhydrous sodium acetate (0.188 g, 2.29 mmol) were combined in ethanol (2.9 mL) and heated at 70° C. for 15 hours. After cooling to room temperature, the reaction mixture was partitioned between methylene chloride and water. The organic phase was washed with water and brine. Each aqueous phase was back extracted with a second portion of methylene chloride. The two organic phases were combined, dried over sodium sulfate and concentrated in vacuo. Purification by flash chromatography, eluting with a 5-40% ethyl acetate-hexanes gradient, yielded 1-cyclohexyl-5-trifluoromethyl-1H-pyrazole-4-carboxylic acid ethyl ester (0.270 g, 55%). Mass spectrum: m/z: 291.3 (M+H).

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