Hydrochloric Acid → (1R)-2-[[2-(4-bromophenyl)ethyl]amino]-1-(3-pyridyl)ethanol dihydrochloride

Temperature

60 °C

To a mixture of 2-(4-bromophenyl)-N-[(2R)-2-hydroxy-2-(3-pyridyl)ethyl]acetamide (160 g) in tetrahydrofuran (1.6 l) was added dropwise 2M borane-dimethylsulfide complex in tetrahydrofuran (716 ml) below 0° C. over 5 hours. The mixture was warmed up to 60° C. and stirred at the same temperature for 3 hours. The reaction mixture was cooled in ice bath (below 5° C.). To the cooled reaction mixture were added methanol and conc. hydrochloric acid (hydrogen gas was evolved). The mixture was heated and stirred at 60° C. for 1 hour, stood overnight at ambient temperature. The mixture was concentrated in vacuo and water was removed as azeotrope with butanol (480 ml). The concentrate was pulverized with isopropyl ether (1.5l). The precipitate was collected by filtration, washed with isopropyl ether and dried in vacuo to give (1R)-2-[[2-(4-bromophenyl)ethyl]amino]-1-(3-pyridyl)ethanol dihydrochloride (226 g).

1. temperatureThe reaction mixture was cooled in ice bath (below 5° C.)
2. customTo the cooled reaction mixture
3. temperatureThe mixture was heated
4. stirringstirred at 60° C. for 1 hour
5. waitstood overnight at ambient temperature
6. concentrationThe mixture was concentrated in vacuo and water
7. customwas removed as azeotrope with butanol (480 ml)
8. filtrationThe precipitate was collected by filtration
9. washwashed with isopropyl ether
10. customdried in vacuo

ORD record

ord-6c28180ed6554f198a9b95a9deecfb1a

Source dataset

uspto-grants-2008_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07417060B2