Реакция #41161

Уравнение реакции

(Tetrahydro-pyran-4-yl)-hydrazine hydrochloride

ethyl (ethoxymethylene)-cyanoacetate

sodium acetate

→

5-amino-1-(tetrahydro-pyran-4-yl)-1H-pyrazole-4-carboxylic acid ethyl ester

Выход 92.3%

Растворители

ethanol

Условия реакции

Обработка

1. 1
   ТемператураAfter cooling to room temperature
2. 2
   Концентрированиеthe reaction was concentrated
3. 3
   Другоеthe residue was partitioned between methylene chloride and water
4. 4
   ДругоеThe organic phase was separated
5. 5
   Промывкаwashed with water
6. 6
   ЭкстракцияEach aqueous phase was back extracted with methylene chloride
7. 7
   Сушкаdried over sodium sulfate
8. 8
   Концентрированиеconcentrated in vacuo
9. 9
   ДругоеThe crude material was purified by flash chromatography
10. 10
    Промывкаeluting with 60-100% ethyl acetate/hexanes

Методика

(Tetrahydro-pyran-4-yl)-hydrazine hydrochloride (1.975 g, 12.94 mmol), ethyl (ethoxymethylene)-cyanoacetate (1.958 g, 11.57 mmol) and sodium acetate (1.370 g; 16.70 mmol) were combined in ethanol (16 mL). The mixture was heated at 80-85° C. for 17 hours. After cooling to room temperature, the reaction was concentrated and the residue was partitioned between methylene chloride and water. The organic phase was separated and washed with water and then brine. Each aqueous phase was back extracted with methylene chloride. The two organic phases were combined, dried over sodium sulfate and concentrated in vacuo. The crude material was purified by flash chromatography eluting with 60-100% ethyl acetate/hexanes to give 5-amino-1-(tetrahydro-pyran-4-yl)-1H-pyrazole-4-carboxylic acid ethyl ester (2.554 g, 92%).

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