反应详情

403 mg (1.47 mmol) of methyl (R)-3-[4-(trifluoromethyl)phenylamino]-pentanoate produced in Example 12 was dissolved in methanol (20 mL) and further mixed with a 28 wt % aqueous ammonia solution (30 mL) at room temperature. After stirring at the same temperature for further 63 hours, the reaction solution was concentrated under reduced pressure and subjected to extraction with ethyl acetate. The product was then dried with anhydrous magnesium sulfate. The residue obtained by removing the solvent by distillation under reduced pressure was purified on silica gel column chromatography to obtain (R)-3-[4-(trifluoromethyl)phenylamino]-pentanoic acid amide as a white solid (183 mg, isolated yield: 48%). The optical purity of the product was determined by HPLC analysis (column; Daicel Chiral Pack AD-H 4.6×250 mm: eluent; hexane/isopropanol=95/5: flow rate; 1.0 mL/min: column temperature; 30° C.: detector; UV 210 nm: retention time; (S) antipode=23.5 minutes, (R) antipode=24.8 minutes) to be 100% ee. 1H-NMR (CDCl3, 400 MHz/ppm): δ 0.98 (3H, t), 1.65 (2H, m), 2.45 (2H, d), 3.76 (1H, m), 4.28 (1H, d), 5.58 (2H, brs), 6.64 (2H, d), 7.38 (2H, d)

1. concentrationthe reaction solution was concentrated under reduced pressure
2. extractionsubjected to extraction with ethyl acetate
3. dry with materialThe product was then dried with anhydrous magnesium sulfate
4. customThe residue obtained
5. customby removing the solvent
6. distillationby distillation under reduced pressure
7. customwas purified on silica gel column chromatography
8. customto obtain