Hydrochloric Acid → (4-Bromo-2-methylphenyl)hydrazine hydrochloride

Participants

Reaction Steps

To a solution of 4-bromo-2-methylaniline (2.50 g, 13.44 mmol) in concentrated HCl (5.4 mL) at 0° C. was added a cold solution of sodium nitrite (1.02 g, 14.78 mmol) in water (5.1 mL). Stirring was continued at 0° C. for 45 min then the mixture was filtered. To the filtrate at 0° C. was added a solution of tin(II) chloride in concentrated HCl (9.5 mL). The reaction mixture was allowed to warm to ambient temperature and stirred overnight. The reaction mixture was made basic at 0° C. with 40% NaOH solution and extracted three times with diethyl ether. The combined organic extracts was washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The resulting solid was treated with 1.25 M HCl in methanol (30 mL), stirred for 10 min at 0° C. then concentrated in vacuo to give a pale yellow solid. The solid was triturated with diethyl ether and dried in vacuo to give (4-bromo-2-methylphenyl)hydrazine hydrochloride (2.26 g, 71%) as an off-white solid: 1H NMR (DMSO-d6, 300 MHz): δ 10.27 (br s, 3H), 7.97 (br s, 1H), 7.35 (m, 2H), 6.89 (d, J=8.2 Hz, 1H), 2.18 (s, 3H).

Provenance & Evidence