6,7-Dimethoxy-1,2,3,4-Tetrahydroisoquinoline → (+/-)-6,7-Dimethoxy-2-{[1-(tert-butyloxycarbonyl)-3-piperidyl]carbonyl}-1,2,3,4-tetrahydroisoquinoline

Participants

Role	Name	HCID	Charge
Reactant	6,7-Dimethoxy-1,2,3,4-Tetrahydroisoquinoline	HCID 15623	—
Reactant	1-Hydroxybenzotriazole	HCID 75771	—
Reactant	1,3-Propanediamine, N'-(ethylcarbonimidoyl)-N,N-dimethyl-, monohydrochloride	HCID 2723939	—
Reactant	1-((Tert-butoxy)carbonyl)piperidine-3-carboxylic acid	HCID 2735647	—
Solvent	Dichloromethane	HCID 6344	—
Product	(+/-)-6,7-Dimethoxy-2-{[1-(tert-butyloxycarbonyl)-3-piperidyl]carbonyl}-1,2,3,4-tetrahydroisoquinoline	HCID 18520105	71.2%

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

DOI	10.6084/m9.figshare.5104873.v1
Patent number	US06573279B1
Source dataset	uspto-grants-2003_06
ORD ID	ord-093d16aa59cb4d06882784b3654fd836
Source note	uspto-grants-2003_06