Реакция #69537

Уравнение реакции

ammonium chloride

tert-butyl(6-methylpyrazolo[5,1-b][1,3]thiazol-7-yl)carbamate

n-butyllithium

1,2-dibromotetrafluoroethane

→

title compound

Выход 91.1%

tert-Butyl(3-bromo-6-methylpyrazolo[5,1-b][1,3]thiazol-7-yl)carbamate

Выход 91.1%

Растворители

tetrahydrofuran

Условия реакции

Обработка

1. 1
   workup.STIRRINGstirred at room temperature for one hour
2. 2
   Экстракцияa substance of interest was extracted with ethyl acetate
3. 3
   ПромывкаThe organic layer was washed with brine
4. 4
   Сушкаdried over magnesium sulfate
5. 5
   workup.DISTILLATIONthe solvent was distilled off under reduced pressure
6. 6
   ДругоеThe residue was purified by medium pressure silica gel column chromatography (n-heptane/ethyl acetate

Методика

A tetrahydrofuran (40 mL) solution of tert-butyl(6-methylpyrazolo[5,1-b][1,3]thiazol-7-yl)carbamate (1.20 g, 4.74 mmol) was cooled to −78° C., and n-butyllithium (1.57 M, 6.64 mL, 10.4 mmol) was added dropwise thereto, and the mixture was stirred for 30 minutes. Then, 1,2-dibromotetrafluoroethane (619 μl, 5.21 mmol) was added to the mixture, and the reaction mixture was warmed to room temperature, and stirred at room temperature for one hour. To the reaction mixture, a saturated aqueous solution of ammonium chloride was added, and a substance of interest was extracted with ethyl acetate. The organic layer was washed with brine and dried over magnesium sulfate, and the solvent was distilled off under reduced pressure. The residue was purified by medium pressure silica gel column chromatography (n-heptane/ethyl acetate: 50% then 66%) to obtain 1.39 g (4.32 mmol) of the title compound.

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