反应详情

To a stirred solution of tert-butyl ethyl (5-nitropyridin-2-yl)malonate (6.93 g, 22.3 mmol, step 1 of Example 1) in dichloromethane (75 mL) was added trifluoroacetic acid (7.64 g, 67.0 mmol) at room temperature, and the mixture was stirred at room temperature for 20 h. The mixture was washed with saturated aqueous sodium hydrogencarbonate solution, dried over magnesium sulfate and concentrated under reduced pressure. The resulting residue was chromatographed on a column of silica gel eluting with n-hexane/ethyl acetate (5:1 to 4:1) to give 3.27 g (70%) of the title compound as an orange oil.

1. washThe mixture was washed with saturated aqueous sodium hydrogencarbonate solution
2. dry with materialdried over magnesium sulfate
3. concentrationconcentrated under reduced pressure
4. customThe resulting residue was chromatographed on a column of silica gel eluting with n-hexane/ethyl acetate (5:1 to 4:1)