반응 #4453

반응 방정식

methyl-3-methoxyisonicotinoate

methyl acetate

hydrochloric acid

sodium bicarbonate

Sodium

sodium

→

3-methoxy-4-acetylpyridine

수율 46.3%

용매

methanol

water

methanol

반응 조건

후처리

1. 1
   기타was removed by distillation
2. 2
   온도The resulting sodium methoxide was cooled
3. 3
   workup.ADDITIONwas added dropwise
4. 4
   온도The mixture was refluxed for four hours
5. 5
   온도to cool
6. 6
   온도The resulting mixture was heated
7. 7
   온도to reflux for 2.5 hours
8. 8
   온도cooled
9. 9
   추출The mixture was extracted with chloroform (4×50 mL)
10. 10
    건조the combined extracts dried over sodium sulfate
11. 11
    농축concentrated
12. 12
    기타chromatographed through a short column of silica gel

실험 절차

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.

출처