[Synthesis]
The general procedure for the synthesis of 3-bromo-4-fluorophenylacetonitrile from 3-bromo-4-fluorobenzyl bromide and sodium cyanide was as follows: sodium cyanide (1.16 g, 22.4 mmol) was added to a solution of 2-bromo-4-(bromomethyl)-1-fluorobenzene (5.0 g, 18.7 mmol) in DMSO (80 mL), and the reaction was stirred for 18 hours at room temperature. After completion of the reaction, the reaction mixture was poured into ethyl acetate and washed four times with 5% NaCl solution. The organic layer was separated, dried with anhydrous magnesium sulfate, filtered and concentrated under reduced pressure to give the crude product as an oil. Purification by silica gel column chromatography afforded 3-bromo-4-fluorophenylacetonitrile as a light amber oil (3.6 g, 75% yield).LC/MS analytical conditions: gradient elution with 90% CH3CN/H2O over 10 min over 5 min, retention time 2.57 min, m/z 214, 216 (M + H).1H NMR (400 MHz. CDCl3) δ ppm: 3.73 (s, 2H), 7.15 (t, J = 8.40 Hz, 1H), 7.20-7.32 (m, 1H), 7.56 (dd, J = 6.25, 2.35 Hz, 1H). |