Sodium Thiosulfate → 2-(Bromomethyl)-3-(trifluoromethyl)pyridine

To a solution of 2-methyl-3-trifluoromethyl-pyridine (0.850 g, 5.28 mmol) (Ashimori, A. et al. Chem. Pharm. Bull. 1990, 33, 2446-2458) in CCl4 (30 mL) was added 1,1′-azobis(cyclohexanecarbonitrile) (0.193 g, 0.79 mmol) and NBS (1.96 g, 11.0 mmol). The mixture was stirred and heated at reflux for 24 h, and then cooled to room temperature. A solution of Na2S2O3 (5 g) in H2O (100 mL) was added, and the organic layer was collected. The aqueous layer was extracted with CH2Cl2 (3×40 mL), and the extracts were combined and dried over anhydrous Na2SO4. After filtration the solvent was removed by evaporation under vacuum, and the residue was purified by flash chromatography on a silica gel column (CH2Cl2), affording 2-bromomethyl-3-trifluoromethyl-pyridine as a pale yellow liquid (0.180 g, 14%). 1H NMR (CDCl3) δ 4.69 (s, 2H), 7.37 (dd, 1H, J=4.5, 7.8 Hz), 7.96 (d, 1H, J=7.8 Hz), 8.78 (d, 1H, J=4.5 Hz).

1. temperatureheated
2. temperatureat reflux for 24 h
3. customthe organic layer was collected
4. extractionThe aqueous layer was extracted with CH2Cl2 (3×40 mL)
5. dry with materialdried over anhydrous Na2SO4
6. filtrationAfter filtration the solvent
7. customwas removed by evaporation under vacuum
8. customthe residue was purified by flash chromatography on a silica gel column (CH2Cl2)

ORD record

ord-7b1c5a6b38b5443bbf893add48041157

Source dataset

uspto-grants-2011_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07863293B2