反应详情

温度

120 °C

3-Nitro-2-pyridinecarbaldehyde (22 g, 144.74 mmol) was dissolved in toluene (500 mL). To the mixture was added catalytic amount of p-TSA (2 g) and ethylene glycol (40 mL) and the reaction flask equipped with Dean-Stark assembly was refluxed for 12 h at 120° C. After the reaction was complete, the reaction mixture was treated with water and ethyl acetate. The organic layer was separated and the aqueous layer was back extracted with ethyl acetate. The organic layers were combined and dried over anhydrous Na2SO4 and concentrated under reduced pressure to give a thick oily mass. The oily mass was then purified by silica gel column chromatography using 20% of ethyl acetate and hexane as eluent to give 2-(1,3-dioxolan-2-yl)-3-nitropyridine: 1H-NMR (CDCl3) δ: 4.2 (d, 5H), 6.5 (s, 1H), 7.5 (m, 1H), 8.3 (d, 1H), 8.9 (brs, 1H).

1. customthe reaction flask equipped with Dean-Stark
2. customThe organic layer was separated
3. extractionthe aqueous layer was back extracted with ethyl acetate
4. dry with materialdried over anhydrous Na2SO4
5. concentrationconcentrated under reduced pressure
6. customto give a thick oily mass
7. customThe oily mass was then purified by silica gel column chromatography