反应详情

To concentrated H2SO4 (100 ml) was added a solution of (1R, 2S)-1-(3,4-difluorophenyl)-2-[[(1R)-2-hydroxy-1-methylethyl]amino]propanol (17.1 g, 0.07 mole) in dichloromethane (100 ml). The reaction was worked up as in Example 1 to yield the crude reaction product as the free base. The crude product was dissolved in diethyl ether and treated with ethereal hydrogen chloride. The hydrochloride salt was recrystallized from ethanol-diethyl ether mixtures to give 9.2 g (49.8% of theory) of (2S, 3S, 5R)-2-(3,4-difluorophenyl)-3,5-dimethylmorpholine hydrochloride as a white solid. m.p. 318° C. [α]20D =+24.6° (c=0.710, 95% ethanol).

1. customto yield the crude
2. customreaction product as the free base
3. customThe hydrochloride salt was recrystallized from ethanol-diethyl ether mixtures