Hydrochloric Acid → HCID 20323730, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 3,4-dihydroxyphenethylamine hydrochloride (1.37 g.), 2-benzimidazolylaminoacetaldehyde diethyl acetal (2.0 g.) and conc. hydrochloric acid (0.8 ml.) in a mixture of n-butanol (7 ml.) and water (3 ml.) was stirred for 10 hours at 110° C. The reaction mixture was allowed to stand at ambient temperature and precipitating crystals were collected by filtration and washed with a mixture of methanol and ether to give crystals (2.92 g.). The crystals were dissolved in water and the solution was neutralized by adding sodium bicarbonate and extracted 3 times with methyl ethyl ketone. The combined extracts were washed with a saturated sodium chloride aqueous solution and dried over magnesium sulfate. The solvent was distilled off to give oil, which was dissolved in methanol (10 ml.). Fumaric acid (0.7 g.) was added thereto and the mixture was stirred and allowed to stand to precipitate crystals. The crystals were collected by filtration and washed with methanol to give 1-(2-benzimidazolyl)aminomethyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline fumarate (2.2 g.). This material was recrystallized from a mixture of dimethylsulfoxide and water to give pure compound (1.0 g.), mp 257° to 259° C (dec.).

Provenance & Evidence