Hydrogen Bromide → 4-Bromo-2-fluoro-3-methylbenzonitrile

Participants

Reaction Steps

A mixture of dimethyl sulfoxide (400 mL) and potassium nitrite (22.67 g, 266 mmol) was stirred to dissolve potassium nitrite and 4-amino-2-fluoro-3-methylbenzonitrile (10 g, 66.6 mmol) and copper(I) bromide (1.911 g, 13.32 mmol) were added. Aqueous 48% hydrogen bromide (33 mL, 266 mmol), diluted with dimethyl sulfoxide (200 mL), was added dropwise and the reaction stirred for 2 h. After complete conversion of starting material, the reaction mixture was poured into iced-cold water and neutralized to pH 7 with cold concentrated sodium hydroxide. The resulting solid was collected by filtration to give the desired product (11.4 g, 53.3 mmol, 80% yield) as white solid. 1H NMR (400 MHz, CHLOROFORM-d) δ (ppm) 7.47 (d, J=9.37 Hz, 1H), 7.33 (t, 1H), 2.39 (d, J=2.34 Hz, 3H).

Provenance & Evidence