Реакция #2186224

Уравнение реакции

potassium hydrogensulfate

sodium hydride

1-(2,6-dichloro-4-trifluoromethylphenyl)-5-hydroxy-4-trifluoromethylthio-1H-pyrazole-3-carbonitrile

diethyl sulfate

→

1-(2,6-dichloro-4-trifluoromethylphenyl)-5-ethoxy-4-trifluoromethylthio-1 H-pyrazole-3-carbonitrile

Выход 70.0%

Растворители

dioxane

dioxane

Условия реакции

Обработка

1. 1
   Температураwas heated
2. 2
   Температураto reflux
3. 3
   Температураheated
4. 4
   Температураunder reflux for 6 hours
5. 5
   Экстракцияextracted with dichloromethane
6. 6
   Сушкаthe organic phase dried over magnesium sulfate
7. 7
   Другоеevaporated
8. 8
   ДругоеThe resulting gum was triturated with pentane

Методика

To a stirred suspension of sodium hydride (0.41 g, 60%, 10.3 mmol) in dioxane (150 ml) was added a solution of 1-(2,6-dichloro-4-trifluoromethylphenyl)-5-hydroxy-4-trifluoromethylthio-1H-pyrazole-3-carbonitrile (4.00 g, 8.53 mmol) in dioxane (50 ml). After gas evolution had ceased the mixture was heated to reflux and diethyl sulfate (1.25 ml, 9.47 mmol) added, and then heated under reflux for 6 hours. The cooled mixture was acidified with aqueous potassium hydrogensulfate (5%), extracted with dichloromethane, and the organic phase dried over magnesium sulfate and evaporated. The resulting gum was triturated with pentane to give 1-(2,6-dichloro-4-trifluoromethylphenyl)-5-ethoxy-4-trifluoromethylthio-1 H-pyrazole-3-carbonitrile (2.68 g, yield 70 %) as off-white crystals, mp 106° C., 1H NMR (CDCl3): 1.36 (t, 3H, CH3), 4.71 (q, 2H, OCH2), and 7.76 (s, 2H, Ar—H).

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