反应详情

A solution of KOH (0.37 g, 6.54 mmol) in ethanol (5 mL) was added to a solution of 2-(6-tert-butoxycarbonylamino-pyridin-3-ylmethyl)-malonic acid diethyl ester (2.18 g, 5.95 mmol) in ethanol (25 mL) and methylene chloride (10 mL) at 0° C. The mixture was stirred for 18 h at room temperature. The mixture was concentrated under reduced pressure and the residue dissolved in water. The aqueous layer was washed with ether, acidified to pH 4 by 1M HCl and extracted with methylene chloride. The organic layer was washed with water, brine and dried. After filtration and concentration under reduced pressure, the crude product was purified by flash chromatography (methanol/CH2Cl2, 1:20) to yield 2-(6-tert-butoxycarbonylamino-pyridin-3-ylmethyl)-malonic acid monoethyl ester (1.00 g, 50%).

1. concentrationThe mixture was concentrated under reduced pressure
2. dissolutionthe residue dissolved in water
3. washThe aqueous layer was washed with ether
4. extractionextracted with methylene chloride
5. washThe organic layer was washed with water, brine
6. customdried
7. filtrationAfter filtration and concentration under reduced pressure
8. customthe crude product was purified by flash chromatography (methanol/CH2Cl2, 1:20)