Aluminum(III) Chloride → 1-Methyl-1,2,3,4-tetrahydroisoquinoline

Temperature

140 °C

50.0 g (161.8 mmole) of N-(2-bromoethyl)-α-methylbenzylamine hydrobromide produced in Example 5(2) above was suspended in 450 ml of decalin and then heated to 140° C. 64.70 g (485.4 mmole) of anhydrous aluminum chloride (AlCl3) was added thereto over 40 minutes. The reaction solution was stirred for a further 30 minutes at constant temperature, and then cooled to room temperature. The supernatant was removed and the lower layer was added to 800 g of ice-water with stirring. 150 ml of con. hydrochloric acid was added thereto and the mixture was stirred for 10 minutes. This solution was washed three times, each time with 1000 ml of ethyl acetate, and the resulting aqueous layer was separated, adjusted to pH 12 with sodium hydroxide, and then extracted three times, each time with 2100 ml of ethyl acetate. The extracts were combined, washed with 420 ml of saturated saline, dehydrated with anhydrous magnesium sulfate, and then evaporated under reduced pressure to remove ethyl acetate. The residue was distilled to obtain 18.1 g of the title compound.

1. temperaturecooled to room temperature
2. customThe supernatant was removed
3. additionthe lower layer was added to 800 g of ice-water
4. stirringwith stirring
5. additionhydrochloric acid was added
6. stirringthe mixture was stirred for 10 minutes
7. washThis solution was washed three times
8. customeach time with 1000 ml of ethyl acetate, and the resulting aqueous layer was separated
9. extractionextracted three times
10. washwashed with 420 ml of saturated saline
11. customevaporated under reduced pressure
12. customto remove ethyl acetate
13. distillationThe residue was distilled

ORD record

ord-ed2aa6b869ce4f11ac9b09eaa592da9c

Source dataset

uspto-grants-2001_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06252076B1