تفاعل #69540

معادلة التفاعل

1,2-dibromotetrafluoroethane

ammonium chloride

n-butyllithium

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

→

title compound

المردود 66.9%

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

المردود 66.9%

المذيبات

acetic acid

n-heptane ethyl acetate

ethyl acetate

THF

ظروف التفاعل

المعالجة

1. 1
   workup.STIRRINGAfter stirring the mixture at −78° C. for 40 minutes
2. 2
   workup.STIRRINGthe mixture was stirred for two hours
3. 3
   درجة الحرارةwhile warming to mom temperature
4. 4
   workup.STIRRINGAfter thoroughly shaking the mixture
5. 5
   أخرىthe organic layer was separated
6. 6
   غسيلthe organic layer was washed with brine
7. 7
   تجفيفdried over anhydrous magnesium sulfate
8. 8
   ترشيحThe mixture was filtered
9. 9
   workup.DISTILLATIONthe solvent in the filtrate was distilled off under reduced pressure
10. 10
    أخرىThe residue was purified by silica gel column chromatography (a mixed solvent of n-heptane and ethyl acetate

الإجراء التجريبي

To a mixture of tert-butyl(6-methoxypyrazolo[5,1-b][1,3]thiazol-7-yl)carbamate (16.5 g, 61.4 mmol) and THF (410 mL) was added n-butyllithium (2.77 M n-hexane solution: 62.1 mL, 172 mmol) while stirring at −78° C. After stirring the mixture at −78° C. for 40 minutes, 1,2-dibromotetrafluoroethane (10.2 mL, 86 mmol) was added, and the mixture was stirred for two hours while warming to mom temperature. A saturated aqueous solution of ammonium chloride and ethyl acetate were added to the mixture, and then acetic acid was added so that the mixture became weakly acidic. After thoroughly shaking the mixture, the organic layer was separated and the organic layer was washed with brine and dried over anhydrous magnesium sulfate. The mixture was filtered, and then the solvent in the filtrate was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of n-heptane and ethyl acetate: n-heptane/ethyl acetate=1/0 then 4/1) to obtain the title compound (14.3 g, 41.1 mmol).

المصدر