反应详情

A solution of KOH (0.19 g, 3.43 mmol) in ethanol (5 mL) was added to a solution of 2-(2-tert-butoxycarbonylamino-pyridin4-ylmethyl)-malonic acid diethyl ester (1.20 g, 3.27 mmol) in ethanol (5 mL) and methylene chloride (5 mL) at 0° C. The mixture was stirred for 18 h at room temperature. The mixture was concentrated under reduced pressure and water was added to the residue. The aqueous layer was washed with diethyl 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 evaporation in vacuo, the crude product was purified by flash chromatography (CH3OH/CH2Cl2, 1:20) to yield 2-(2-tert-butoxycarbonylamino-pyridin4-ylmethyl)-malonic acid monoethyl ester (0.90 g, 81%).

1. concentrationThe mixture was concentrated under reduced pressure and water
2. additionwas added to the residue
3. washThe aqueous layer was washed with diethyl ether
4. extractionextracted with methylene chloride
5. washThe organic layer was washed with water, brine
6. customdried
7. filtrationAfter filtration and evaporation in vacuo
8. customthe crude product was purified by flash chromatography (CH3OH/CH2Cl2, 1:20)