Sodium Thiosulfate → 4-Cyano-3-fluorobenzyl bromide

Participants

Reaction Steps

To a solution of 2-fluoro-4-methyl-benzonitrile (1.45 g, 10.7 mmol) in CCl4 (100 mL) was added 1,1′-azobis(cyclohexanecarbonitrile) (0.240 g, 0.982 mmol) and NBS (2.19 g, 12.3 mmol). The mixture was stirred and heated at reflux overnight, 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 (3×50 mL), and the extracts were combined and dried over Na2SO4. After filtration the solvent was removed by evaporation under vacuum, and the residue was purified on silica gel column (1:10 EtOAc/hexanes), affording 4-bromomethyl-2-fluoro-benzonitrile as a pale yellow oil (1.49 g, 65%). 1H NMR (CDCl3) δ 4.45 (s, 2H), 7.24-7.30 (m, 2H), 7.60 (dd, 1H, J=6.3, 8.1 Hz).

Provenance & Evidence