Hydrogen Bromide → (R)-1-Methyl-1,2,3,4-tetrahydroisoquinoline

Participants

Reaction Conditions

Reaction Steps

76.61 g(630 mmole) of (R)-(+)-α-methylbenzylamine was dissolved in 77 ml of dichloromethane and 94.8 g(760 mmole) of 2-bromoethanol was added thereto. This mixture was stirred at 51° C. for 50 hours to complete the reaction. The reaction solution was concentrated under reduced pressure and 286.4 ml(2500 mmole) of 48% aqueous hydrobromic acid solution was added thereto and then allowed to react at 126° C. for 30 minutes under refluxing. The reaction solution was then distilled for 2 hours under normal pressure at constant temperature and 250 ml of aqueous hydrobromic acid and water, the reaction by-product, was removed. The residue was dissolved in 350 ml of isopropyl alcohol with refluxing for 30 minutes, and this solution was cooled to 10° C. and then allowed to stand for 3 hours. The resulting solid product was filtered, washed with 50 ml of ethyl acetate, and then dried to obtain 127.5 g of the title compound.

Provenance & Evidence