تفاعل #712129

معادلة التفاعل

6-chloro-5-bromo-pyridine-2-carboxylic acid

potassium tert-butoxide

2,2,3,3,3-pentafluoropropan-1-ol

Hydrochloric acid

→

title compound

المردود 22.0%

5-Bromo-6-(2,2,3,3,3-pentafluoro-propoxy)-pyridine-2-carboxylic acid

المردود 22.0%

المذيبات

DMF

THF

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةcooled
2. 2
   استخلاصthe mixture was extracted with TBME, organic layers
3. 3
   غسيلwere washed twice with water
4. 4
   تجفيفdried with Na2SO4
5. 5
   ترشيحfiltered
6. 6
   تركيزconcentrated in vacuo
7. 7
   أخرىThe crude material was purified by flash chromatography (silica gel, ethyl acetate/n-heptane gradient)

الإجراء التجريبي

To a solution of 6-chloro-5-bromo-pyridine-2-carboxylic acid (CAN 959958-25-9, 1.7 g, 7.19 mmol) in DMF (90 mL) and THF (30 mL) was added potassium tert-butoxide (2.02 g, 18.0 mmol) and 2,2,3,3,3-pentafluoropropan-1-ol (5.73 mL, 57.5 mmol). The mixture was stirred at 140° C. for 4 days, cooled and poured into ice-water (100 mL). 2 M Hydrochloric acid (15 mL) was added to adjust the pH to 2-3 and the mixture was extracted with TBME, organic layers were washed twice with water, pooled, dried with Na2SO4, filtered and concentrated in vacuo. The crude material was purified by flash chromatography (silica gel, ethyl acetate/n-heptane gradient) to give the title compound (548 mg, 22%) as light-brown solid; LC-MS (UV peak area, ESI) 100%, 347.9306 [M−H−].

المصدر