Hydrochloric Acid → 2-butylbenzofuran-5-amine Hydrochloride

Participants

Reaction Steps

Sodium bicarbonate (3.36 g, 40.0 mmol) was added in several portions to a stirred boiling mixture of N-[3-(2-bromohexanoyl)-4-hydroxyphenyl]acetamide [6a] (13.13 g, 40.0 mmol) and methanol (30 mL). The mixture was stirred under reflux conditions for 2 hour. Sodium borohydride (1.51 g, 40.0 mmol) was added in several portions to the mixture at 0-5° C. (ice/water bath). The mixture was stirred for 30 min at the same temperature and 15% hydrochloric acid (100 mL) was added. The solution was stirred for 4 hours under reflux conditions and for 1 hour at 0-5° C. (ice/water bath). The precipitated crystals were filtered off, washed on the filter with water (20 mL) and ethyl acetate (20 mL) and dried to give 7.62 g (84.5% yield from 3 steps) of 2-butyl-5-benzofuranamine hydrochloride [12a] as off-white crystals with mp 190-193° C. (dec.).

Provenance & Evidence