Hydrochloric Acid → (+/-)-6,7-Dimethoxy-2-[(3-piperidyl)carbonyl]-1,2,3,4-tetrahydroisoquinoline hydrochloride

Participants

Reaction Steps

A conventional amidation reaction was carried out using a dichloromethane solution (40 ml) of 2.53 g of (±)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline, 3.0 g of N-(tert-butyloxycarbonyl)nipecotic acid, 3.0 g of 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide hydrochloride and 0.89 g of 1-hydroxybenztriazole to give 3.77 g of (±)-6,7-dimethoxy-2-{[1-(tert-butyloxycarbonyl)-3-piperidyl]carbonyl}-1,2,3,4-tetrahydroisoquinoline. Deprotection of 3.77 g of (±)-6,7-dimethoxy-2-{[1-(tert-butyloxycarbonyl)-3-piperidyl]carbonyl}-1,2,3,4-tetrahydroisoquinoline was further carried out using 10 ml of an ethyl acetate solution containing 4N hydrochloric acid to give 2.30 g of (±)-6,7-dimethoxy-2-[(3-piperidyl)carbonyl]-1,2,3,4-tetrahydroisoquinoline hydrochloride as colorless crystals.

Provenance & Evidence