1,2,3,4-Tetrahydroisoquinoline → 6,7-Dimethoxy-3',4'-dihydro-1'H-[1,2']biisoquinolinyl

Participants

Reaction Steps

Palladium acetate (25 mg 0.112 mmol) and 2,2′-bis(diphenylphosphino)-1,1′-binaphtyl (209 mg, 0.335 mmol) were heated to 80° C. in toluene (25 mL) for 20 min. To the mixture was added 500 mg (2.24 mmol) of 1-chloro-6,7-dimethoxy-isoquinoline, 298 mg (2.24 mmol) of tetrahydroisoquinoline, and 4.47 mL (4.47 mmol) of a 1.0 M solution of potassium tert-butoxide in THF. After stirring at reflux for 4 h, the mixture was diluted with EtOAc, washed with water, dried over MgSO4 and concentrated. Silica gel chromatography (4:1 hexanes/EtOAc) provided 625 mg (87%) of the title compound as a yellow oil. The hydrochloride salt (387 mg) was obtained after treatment with concd. HCl in isopropanol and recrystallization from EtOH/MeOH.

Provenance & Evidence