反应详情

To a solution of methyl 6-methylnicotinate (6.05 g) in methylene chloride (100 mL) was added m-chloroperbenzoic acid (77%, 13.5 g). The reaction mixture was stirred at room temperature for 2 h and then diluted with chloroform (100 mL). The mixture was washed successively with aqueous sodium sulfite, saturated sodium bicarbonate, and brine. The organic later was then dried (sodium sulfate), filtered, and concentrated under reduced pressure to provide 6.21 g of methyl 6-methylnicotinate 1-oxide. A solution of methyl 6-methylnicotinate 1-oxide (4.35 g) in acetic anhydride (50 mL) was heated at 120° C. for 2 h and then concentrated under reduced pressure. Purification by flash column chromatography (silica gel, 1:2 to 3:5 ethyl acetate/hexanes) provided 3.3 g of the title compound: 3H NMR (300 MHz, CDCl3) δ 9.18, 8.31, 7.44, 5.29, 3.96, 2.19.

1. washThe mixture was washed successively with aqueous sodium sulfite, saturated sodium bicarbonate, and brine
2. dry with materialThe organic later was then dried (sodium sulfate)
3. filtrationfiltered
4. concentrationconcentrated under reduced pressure