Ethanol → 2-(Aminomethyl)-4-bromoaniline

Participants

Reaction Steps

A solution of borane in THF (1 M, 400 ml) was added at 0° C. to a suspension of 5-bromo-anthranilonitrile (60 g, 0.304 mol, prepared as described in S. M. Mackenzie et al, J. Chem. Soc. C, 1970, 17, 2298-2308) in THF (450 L), under N2. The mixture was stirred for 72 hours at r.t. After cooling at 0° C. absolute EtOH was added, then HCl was bubbled through the solution. The mixture was concentrated and the residue was suspended in isopropyl ether. The obtained solid was dried to give the di-hydrochloride of the title product (76.6 g, 91.4% yield). C7H9BrN2. 2HCl, MW 273.9; 1H-NMR (200 MHz, d6-DMSO) ppm: 4.13 (s, 2H); 5.82 (s, 4H), 7.24 (d, 1H), 7.55 (dd, 1H), 7.73 (s, 1H), 8.57 (s, 2H). Since the free base is used in the cyclization step, the hydrochloride was suspended in aqueous ammonia, stirred for some minutes after that the free base precipitates. The solid is filtered and dried (yield is quantitative).

Provenance & Evidence