3-Acetylpyridine → Methyl 2,4-dioxo-4-(pyridin-3-yl)butanoate

関与物質

反応手順

Sodium methoxide (5.4 g, 100 mmol) and dimethyloxalate (11.8 g, 100 mmol) were dissolved in anhydrous methanol (700 mL) and stirred at room temperature under nitrogen until a suspension was formed. To this mixture, 3-acetylpyridine (5.5 mL, 50 mmol) was added and the stirring was continued for 3 days at room temperature. The reaction was quenched with enough 5% aqueous KHSO4 until all solids have dissolved. The methanol was removed under reduced pressure, and the residue was extracted with ethyl acetate (3×200 mL). The combined organic layers were washed with water (2×200 mL), brine and dried (NaSO4) followed by the removal of solvent under reduced pressure to give the title compound (8.67 g, 84% yield) as a yellow solid. 1H NMR (CDCl3, 300 MHz) δ 9.21–9.20 (m, 1H), 8.84–8.82 (m, 1H), 8.30–8.26 (m, 1H), 7.50–7.45 (m, 1H), 7.08 (s, 1H), 3.96 (s, 3H). 13C NMR (CDCl3, 75 MHz) δ 188.5, 170.4, 162.2, 153.9, 149.0, 135.2, 130.5, 123.8, 98.0, 53.3. mass spectrum (APIMS) m/z 208 (M+1)+.

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