反应详情

Nitric acid (100 ml) and 3-methyl-N-(2-pyridyl)aniline (Hirota, M.; Kobayashi, K. Bull Chem. Soc. Jpn. 1981, 54, 1583) (16.8 g, 91.2 mmol) was mixed with ice cooling, the ice bath was removed and the reaction mixture was stirred for 40 h at room temperature. The reaction mixture was poured into saturated aqueous sodium bicarbonate solution (200 ml), the aqueous mixture was basified with the addition of potassium carbonate and the resulting basic solution was extracted with ethyl acetate (500 ml). The organic extracts were washed with water (50 ml) and brine (50 ml), dried (magnesium sulfate) and concentrated to dryness. The residue was purified by column chromatography (silica gel, 350 g; n-hexane/ethyl acetate (9/1)) to give 3.85 g (18%) of the titled compound as yellow solids. 1H-NMR (CDCl3) δ: 10.21 (1H, br.s), 8.54 (1H, s), 8.38-8.32 (1H, m), 8.13 (1H, d J=8.8 Hz), 7.68-7.60 (1H, m), 6.98-6.92 (2H, m), 6.80-6.70 (1H, m), 2,42 (3H, s).

1. customthe ice bath was removed
2. additionThe reaction mixture was poured into saturated aqueous sodium bicarbonate solution (200 ml)
3. additionthe aqueous mixture was basified with the addition of potassium carbonate
4. extractionthe resulting basic solution was extracted with ethyl acetate (500 ml)
5. washThe organic extracts were washed with water (50 ml) and brine (50 ml)
6. dry with materialdried (magnesium sulfate)
7. concentrationconcentrated to dryness
8. customThe residue was purified by column chromatography (silica gel, 350 g; n-hexane/ethyl acetate (9/1))