Hydrogen Bromide → 1-Methyl-1,2,3,4-tetrahydroisoquinoline

Temperature

51 °C

76.61 g(630 mmole) of 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 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 128.9 g of the title compound.

1. customthe reaction
2. additionwas added
3. customto react at 126° C. for 30 minutes
4. temperatureunder refluxing
5. distillationThe reaction solution was then distilled for 2 hours under normal pressure at constant temperature and 250 ml of aqueous hydrobromic acid and water
6. customthe reaction by-product, was removed
7. dissolutionThe residue was dissolved in 350 ml of isopropyl alcohol
8. temperaturewith refluxing for 30 minutes
9. temperaturethis solution was cooled to 10° C.
10. waitto stand for 3 hours
11. filtrationThe resulting solid product was filtered
12. washwashed with 50 ml of ethyl acetate
13. customdried

ORD record

ord-3ba5382f8c234c77a75caf73d231d62a

Source dataset

uspto-grants-1999_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05990311