反応 #4453

反応方程式

methyl-3-methoxyisonicotinoate

methyl acetate

hydrochloric acid

sodium bicarbonate

Sodium

sodium

→

3-methoxy-4-acetylpyridine

収率 46.3%

溶媒

methanol

water

methanol

反応条件

後処理

1. 1
   その他was removed by distillation
2. 2
   温度The resulting sodium methoxide was cooled
3. 3
   workup.ADDITIONwas added dropwise
4. 4
   温度The mixture was refluxed for four hours
5. 5
   温度to cool
6. 6
   温度The resulting mixture was heated
7. 7
   温度to reflux for 2.5 hours
8. 8
   温度cooled
9. 9
   抽出The mixture was extracted with chloroform (4×50 mL)
10. 10
    乾燥the combined extracts dried over sodium sulfate
11. 11
    濃縮concentrated
12. 12
    その他chromatographed through a short column of silica gel

実験手順

A dry 50 mL three neck flask fitted with a reflux condenser and internal thermometer was charged with dry methanol (20 mL). Sodium (516 mg, 0.022 mol) was added in portions and after all the sodium had dissolved the methanol was removed by distillation. The resulting sodium methoxide was cooled and a mixture of methyl-3-methoxyisonicotinoate (2.50 g, 0.015 mol) and methyl acetate (6.65 g, 0.090 mol) was added dropwise. The mixture was refluxed for four hours, allowed to cool and dissolved in water (9.0 mL) and concentrated hydrochloric acid (6.0 mL). The resulting mixture was heated to reflux for 2.5 hours, cooled, and basified with 5% sodium bicarbonate. The mixture was extracted with chloroform (4×50 mL) and the combined extracts dried over sodium sulfate, concentrated, and chromatographed through a short column of silica gel to afford 3-methoxy-4-acetylpyridine (1.05 g, 46%). mp. 36°-37° C.

出典