4-Bromo-2-methyl-6-nitroaniline → 5-Bromo-3-methylbenzene-1,2-diamine

Participants

Reaction Steps

To a suspension of 4-bromo-2-methyl-6-nitro-phenylamine (20 g, 0.086 mol) in ethanol (200 mL) was added tin chloride dihydrate (49.2 g, 0.258 mol). The reaction mixture was heated to reflux for 14 h, cooled to room temperature, and concentrated in vacuo. The residue was diluted with ethyl acetate (150 mL) and treated with triethylamine (40 mL). The resulting slurry was filtered through a pad of celite, and the filtercake was rinsed with three portions ethyl acetate (50 mL). The filtrate was washed with saturated NaHCO3, water, and brine, then dried over Na2SO4 and filtered. After removal of the solvent, the residue was purified by flash chromatography on silica gel (30% EtOAc/hexane, then 5% MeOH/CH2Cl2) to yield the title compound (10.26 g, 59%) as a yellow oil. 1H NMR (300 MHz, CDCl3) δ 6.77 (1H, d, J=2.0 Hz), 6.74 (1H, d, J=2.0 Hz), 2.16 (3H, s). LCMS (M+H)+ m/z 201. (t=0.83 min.). Procedure for the preparation of 1-[4-(3,4-diamino-5-methyl-phenyl)-piperazin-1-yl]-ethanone

Provenance & Evidence