HCID 14625300, compound → HCID 14625302, compound

Participants

Reaction Steps

A suspension of the product of part (A) (3.0 g) in methanol (400 ml) was warmed at about 50° until the majority of the product dissolved. The reaction mixture was then transferred to a hydrogenator and hydrogenated under a hydrogen pressure of 2.068×105Pa (30 psi) in the presence of 5% Pd/C (400 mg) at room temperature with stirring for 1.5 hours. The reaction mixture was filtered through "Arbacel" (a microcrystalline cellulose filtration aid), and evaporated to yield impure 4-amino-6,7-dimethoxy-2-(6-hydroxy-7-methoxy-1,2,3,4-tetrahydroisoquinol-2-yl)quinoline (600 mg). The catalyst was then stirred in methylene chloride/methanol (4:1, 200 ml) for 30 minutes, and the mixture was filtered and the filtrate evaporated to yield a further 1.05 g of the impure product. The total of the impure product (1.65 g) was dissolved in methylene chloride/methanol (4:1, 300 ml) and shaken with 10% sodium carbonate solution (50 ml). The organic phase was washed (H2O), dried and evaporated. Medium pressure chromatography of the residue on silica (Merck "Art.9385") eluting with methylene chloride containing gradually increasing amounts of ethanol (1-25%) followed by collection and evaporation of appropriate fractions gave the title compound. The compound was slurried in boiling methylene chloride (20 ml), cooled, precipitated with hexane, filtered, and the solid washed with hexane and dried to give the pure title compound as a quarter-hydrate (900 mg), m.p. 250°- 251°.

Provenance & Evidence