تفاعل #9277

معادلة التفاعل

water

n-butyllithiumhexane

2-ethylpyrazolo[1,5-a]pyridine

1,2-dibromo-1,1,2,2-tetrachloroethane

→

title compound

المردود 73.1%

7-Bromo-2-ethylpyrazolo[1,5-a]pyridine

المردود 73.1%

المذيبات

tetrahydrofuran

tetrahydrofuran

ظروف التفاعل

المعالجة

1. 1
   workup.STIRRINGstirring
2. 2
   workup.WAITwas continued for 30 minutes
3. 3
   استخلاصextraction
4. 4
   غسيلthe organic layer was washed with water and brine
5. 5
   تجفيفAfter drying over anhydrous magnesium sulfate and filtration
6. 6
   تركيزthe solvent was concentrated under reduced pressure
7. 7
   أخرىthe residue was purified by silica gel column chromatography

الإجراء التجريبي

After dissolving 2-ethylpyrazolo[1,5-a]pyridine (80 mg) in tetrahydrofuran (1 mL), an n-butyllithiumhexane solution (1.6 M; 0.58 mL) was added dropwise at −78° C. under a nitrogen stream, and the mixture was stirred for 30 minutes. A solution of 1,2-dibromo-1,1,2,2-tetrachloroethane (196 mg) in tetrahydrofuran (0.5 mL) was added to the reaction mixture, and stirring was continued for 30 minutes. The temperature was increased to room temperature, water was added, extraction was performed with ethyl acetate and the organic layer was washed with water and brine. After drying over anhydrous magnesium sulfate and filtration, the solvent was concentrated under reduced pressure, the residue was purified by silica gel column chromatography and the title compound (90 mg) was obtained from the n-hexane:ethyl acetate (20:1) fraction as a light brown oil.

المصدر