Hydrogen Bromide → 3-Bromo-5-nitrobenzoic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-amino-5-nitro-benzoic acid (17.6 g, 96.6 mmol, 1 equiv) in 48% aqueous HBr solution (180 ml) at 0° C. was added portionwise NaNO2 (8.67 g, 126 mmol, 1.3 equiv) over 20 min. The temperature was kept below 8° C. during this addition. The resulting mixture was then added to a suspension of CuBr (9.7 g, 67.6 mmol, 0.7 equiv) in 48% aqueous HBr solution (50 ml) at 65° C. over 40 min. The temperature was kept above 60° C. during the addition. The resulting mixture was stirred at 70° C. for 45 min, cooled to room temperature and diluted with 1 L of water. The aqueous phase was extracted three times with Et2O. The combined organic layers were washed twice with H2O, dried over MgSO4 and concentrated in vacuo to give 3-bromo-5-nitro-benzoic acid (D5) (21 g, 88%) as a brown solid. [M−H]−=245.7, RT=2.82 min

Provenance & Evidence