Hydrochloric Acid → 7-Fluoro-2,3,4,9-tetrahydro-1H-beta-carboline

6-Fluorotryptamine (0.71 g) was dissolved in tetrahydrofuran (30 ml), a 4N hydrochloric acid-ethyl acetate solution (1.2 ml) was added dropwise, and the mixture was stirred at room temperature. The solvent was evaporated under reduced pressure. Glyoxylic acid monohydrate (Aldrich Co., 403 mg), a 1N potassium hydroxide solution (3.98 ml) and water (80 ml) were added to the obtained residue, and the mixture was stirred with heating at 80° C. for 1.5 hr. After ice-cooling, the precipitate was collected by filtration and washed with water to give a pale-brown solid. Water (80 ml) and concentrated hydrochloric acid (2 ml) were added to the obtained solid, and the mixture was stirred with heating at 80° C. for 1 hr. Concentrated hydrochloric acid (2 ml) was further added, and the mixture was heated under reflux for 1 hr. The insoluble material was hot filtrated, and the filtrate was adjusted to pH 12 or above with a 6N aqueous sodium hydroxide solution. The precipitated solid was collected by filtration, washed with water, and dried to give 7-fluoro-2,3,4,9-tetrahydro-1H-β-carboline (516 mg, yield 68%).

1. customThe solvent was evaporated under reduced pressure
2. additionGlyoxylic acid monohydrate (Aldrich Co., 403 mg), a 1N potassium hydroxide solution (3.98 ml) and water (80 ml) were added to the obtained residue
3. stirringthe mixture was stirred
4. temperaturewith heating at 80° C. for 1.5 hr
5. temperatureAfter ice-cooling
6. filtrationthe precipitate was collected by filtration
7. washwashed with water
8. customto give a pale-brown solid
9. stirringthe mixture was stirred
10. temperaturewith heating at 80° C. for 1 hr
11. temperaturethe mixture was heated
12. temperatureunder reflux for 1 hr
13. filtrationThe precipitated solid was collected by filtration
14. washwashed with water
15. customdried

ORD-Eintrag

ord-c10ca2faf9eb499c9614850ab2a3a47a

Quelldatensatz

uspto-grants-2011_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07994196B2