Hydrochloric Acid → 2-Benzyl-8-chloro-7-methoxy-4-(3,4-dimethoxyphenyl)-1,2,3,4-tetrahydroisoquinoline

Participants

Reaction Steps

2.02 g of 8-amino-2-benzyl-7-methoxy-4-(3,4-dimethoxyphenyl)-1,2,3,4-tetrahydroisoquinoline was dissolved in 20% hydrochloric acid; and to the solution was added dropwise a solution of 0.38 g of sodium nitrite in 1.9 ml of water, under cooling. To the mixture was added dropwise a solution of 0.55 g of cuprous chloride in 11 ml of 20% hydrochloric acid. After the reaction was over, 4.84 g of sodium hydroxide was added to the mixture, and the mixture was extracted with chloroform 2 times. The chloroform layer was collected, washed with water, and dried over anhydrous magnesium sulfate. The solvent was distilled off, and the residue was recrystallized from ethanol, giving 1.23 g of 2-benzyl-8-chloro-7-methoxy-4(3,4-dimethoxyphenyl)-1,2,3,4-tetrahydroisoquinoline, m.p. 88°-91° C. ##STR54## 1.13 g of 2-benzyl-8-chloro-7-methoxy-4-(3,4-dimethoxyphenyl)-1,2,3,4-tetrahydroisoquinoline was dissolved in 28 ml of ethanol, and after adding thereto 0.22 ml of 12N hydrochloric acid, hydrogenation reaction was performed by addition of 0.1 g of 10%-paradium-carbon. After the hydrogenation reaction was over, the reaction solution was filtered, and concentrated. The residue was dissolved in chloroform, washed with saturated aqueous sodium hydrogen carbonate solution and water, and dried over anhydrous magnesium sulfate. The solvent was distilled off, and the residue was recrystallized from ethyl acetate-n-hexane, giving 580 mg of 8-chloro-7-methoxy-4-(3,4-dimethoxyphenyl)-1,2,3,4-tetrahydroisoquinoline, m.p. 130°-132° C.

Provenance & Evidence