反应详情

The mixture of ethyl {5-[(tert-butoxycarbonyl)amino]pyridin-2-yl}acetate (3.72 g, 15.6 mmol, step 4 of Example 1) and platinum oxide (300 mg) in ethanol (6 mL) and acetic acid (6 mL) was stirred under hydrogen (4 atom) at room temperature for 8 h. The mixture was filtered through a pad of Celite washing with ethanol and the filtrate was concentrated. The resulting residue was diluted with 2N aqueous sodium hydroxide solution (100 mL), and extracted with dichloromethane (100 mL×3). The combined organic layer was dried over magnesium sulfate, and concentrated under reduced pressure. The resulting residue was chromatographed on a column of silica gel eluting with dichloromethane/methanol (20:1) to give 2.48 g (65%) of the title compound as a colorless oil. (trans isomer 559 mg, 15% yield)

1. filtrationThe mixture was filtered through a pad of Celite
2. washwashing with ethanol
3. concentrationthe filtrate was concentrated
4. additionThe resulting residue was diluted with 2N aqueous sodium hydroxide solution (100 mL)
5. extractionextracted with dichloromethane (100 mL×3)
6. dry with materialThe combined organic layer was dried over magnesium sulfate
7. concentrationconcentrated under reduced pressure
8. customThe resulting residue was chromatographed on a column of silica gel eluting with dichloromethane/methanol (20:1)