Hydrochloric Acid → n-Ethyl n-(2-benzyloxy-5-bromobenzyl)amine hydrochloride salt

Participants

Reaction Conditions

Reaction Steps

Benzyl bromide (71.4 ml) was added dropwise to a mixture of 5-bromo-2-hydroxybenzaldehyde (100.5 g) and K2CO3 (207.5 g) in 1-methyl-2-pyrrolidinone (500 ml) at 30° C. over 1 hour. The mixture was stirred for 3 hours at 35°-40° C. A solution of ethylamine hydrochloride (57.1 g) in methanol (250 ml) was added over 30 minutes at 35° C. and the mixture stirred for 3 hours at 35°-40° C. A solution of sodium borohydride (26.5 g) in 1-methyl-2-pyrrolidinone (300 ml) was added over 2 hours at 35°-40° C. and the mixture stirred at 40°-45° C. for 2 hours. The mixture was cooled (10° C.), diluted with ethyl acetate (200 ml) and acidified with 2N HCl (3,500 ml). The resulting precipitate was filtered off, washed with toluene and 40-60 petroleum ether and dried under vacuum at 60° C. The residue was purified by stirring in a mixture of acetonitrile (140 ml) and toluene (700 ml) at 80° C. for 30 minutes, cooling to 10° C. and filtering off the product to give N-ethyl N-(2-benzyloxy-5-bromobenzyl)amine hydrochloride salt (13.6 g, 76.7% yield).

Provenance & Evidence