反应详情

The above product of 4-(5-fluoro-2-methoxy-phenyl)-piperidine (Intermediate 4) was dissolved in N,N-dimethylformamide (10 mL) at 0° C. To the resulting solution, 0.70 g (2.5 mmole) of 2-[N-methyl-N-(tert-butoxycarbonyl)-amino]-3-phenyl-propionic acid in a minimal amount of DMF was added, followed by 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (DAEC) (0.48 g, 2.5 mmole), 1-hydroxybenzotriazole hydrate (HOBT) (0.41 g, 2.5 mmole) and 4-methylmorpholine (NMM) (0.37 mL, 3.4 mmole) and the mixture was stirred overnight (the reaction temperature was slowly allowed to warm up to room temperature). The reaction mixture was diluted with water (50 mL) and EtOAc (50 mL) and the layers separated. The aqueous layer was washed with HCl (1N), saturated NaHCO3, and the combined aqueous layers were extracted three times with EtOAc. The combined organic layers were dried over Na2SO4 and concentrated. Flash chromatography, gradient elution with 1:4 EtOAc-hexane to 3:7 EtOAc-hexane to afford (R)-{1-benzyl-2-[4-(5-fluoro-2-methoxy-phenyl)-piperidin-1-yl]-2-oxo-ethyl}-methyl-carbamic acid tert-butyl ester as a yellow oil.

1. customthe layers separated
2. washThe aqueous layer was washed with HCl (1N), saturated NaHCO3
3. extractionthe combined aqueous layers were extracted three times with EtOAc
4. dry with materialThe combined organic layers were dried over Na2SO4
5. concentrationconcentrated
6. washFlash chromatography, gradient elution with 1:4 EtOAc-hexane to 3:7 EtOAc-hexane