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

Participants

Reaction Conditions

Reaction Steps

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).

Provenance & Evidence