3-bromo-5-fluoropyridine CAS NO.407-20-5

Hebei Yanxi Chemical Co., Ltd. is a professional research, development and production of lead acetate benzene acetamide enterprise backbone members by local well-known entrepreneurs and professional senior engineers in the party's "low carbon environmental protection safety smooth" call and support form, the bold innovation on traditional production equipment and technology, using "high temperature alkali type production method" and "plastic basin of crystallization technology, on the basis of reducing the product cost make the product quality to achieve the same industry leading level.In the company all staff's efforts, in shandong, henan province guangdong South America Europe the United States for decades in Mexico, Brazil, South Africa, Zimbabwe and other places set up several partners, quality inspection department in the company, under the close supervision of a production and sales in the form of "label", provide the fastest speed convenient service for users across the country.

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About:
5-bromo-3-fluoropyridine is an organic intermediate that can be prepared from 3, 5-dibromo-pyridine by a one-step reaction with NFSI, or from 5-bromo-nicotinamide by a two-step reaction.

Preparation:
Under nitrogen, 3, 5-dibromopyridine (1.21g) was added to a 50mLSchlenk flask containing THF (5.0mL). At 0°C, i-PrMgCl·LiCl (5.5mmol) of THF (1.16M, 4.7mL) was added to the flask. Stir the reaction mixture at 0°C for 1 hour. Vacuum removal of solvent (0.5mbar, 40°C, 0.5 hours). CH2Cl2 (5mL) was added to the reaction mixture and NFSI (1.89g, 6mmol) in CH2Cl2 (15mL) and perfluoronaphthalane (5mL) was slowly added to the reaction mixture at -78°C. Stir the reaction mixture at 0°C for 30 minutes. The reaction mixture was stirred at 25°C for 2 hours, then poured into a cold saturated NH4Cl aqueous solution (50mL), extracted with CH2Cl2 (3×50mL), and dried with Na2SO4. The organic layer was filtered, the organic layer was concentrated under vacuum, the crude residue was purified by column chromatography (SiO2) using pentane /Et2O (20:1) as eluent to obtain 5-bromo-3-fluoropyridine.