Ammonia → 2,5-Dichloro-4-(trifluoromethyl)pyridine

Copper iodide (1.67 g) and potassium fluoride (0.51 g) were subjected to a reduced pressure (1 Torr) using a vacuum pump, and were heated with a heat gun for 20 minutes while stirring slowly. Under the argon atmosphere, 14 ml of N-methylpyrrolidine and 1.25 g of trifluoromethyltrimethylsilane were added, and a temperature was elevated to 50° C. over 20 minutes. After further stirring for 30 minutes, 2 g of 2,5-dichloro-4-iodopyridine was added, and the mixture was stirred for 20 hours. After allowing to cool, the reaction solution was poured into a 12% aqueous ammonia solution, the resultant solution was extracted with diethyl ether three times, washed with an aqueous saturated sodium chloride solution, dried with anhydrous magnesium sulfate, and concentrated. The residue was subjected to silica gel column chromatography to obtain 1 g of 2,5-dichloro-4-trifluoromethylpyridine.

1. temperaturewere heated with a heat gun for 20 minutes
2. stirringAfter further stirring for 30 minutes
3. stirringthe mixture was stirred for 20 hours
4. temperatureto cool
5. extractionthe resultant solution was extracted with diethyl ether three times
6. washwashed with an aqueous saturated sodium chloride solution
7. dry with materialdried with anhydrous magnesium sulfate
8. concentrationconcentrated

ORD record

ord-2dad325d105144bc8656e839b5b8e39d

Source dataset

uspto-grants-2012_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08318776B2