4-Bromo-2-nitrobenzoic acid → 2-Amino-4-bromobenzoic acid

Participants

Reaction Steps

A mixture of Example 125A (5.1 g, 20.7 mmol) in concentrated ammonium hydroxide (102 mL) was treated with a solution of ammonium iron (II) sulfate (49 g, 125.1 mmol) in water (102 mL) over 5 minutes, heated to reflux for 2 minutes, cooled to room temperature, filtered through diatomaceous earth (Celite®), acidified to pH 1 with concentrated HCl, and extracted with ethyl acetate. The organic layer was dried (Na2SO4), filtered, and concentrated to provide the desired product. MS (ESI(−)) m/e 214, 216 (M−H)−, 1H NMR (300 MHz, DMSO-d6) δ 7.59 (d, 1H), 6.97 (d, 1H), 6.63 (dd, 1H), 3.32 (br s, 3H).

Provenance & Evidence