반응 #79182

반응 방정식

2-fluoropyridine

2-methyl-1H-benzimidazole

sodium hydride

→

titled compound

수율 71.3%

2-Methyl-1-(2-pyridyl)-1H-benzimidazole

수율 71.3%

용매

dimethylacetamide

dimethylacetamide

dimethylacetamide

반응 조건

후처리

1. 1
   온도to reflux for about 4 h
2. 2
   기타Volatiles were removed by evaporation under reduced pressure
3. 3
   workup.DISSOLUTIONThe residue was dissolved into ethyl acetate (200 ml)
4. 4
   세척washed consecutively with water (3×100 ml) and brine (100 ml)
5. 5
   건조The organic layer was dried (magnesium sulfate)
6. 6
   농축concentrated to dryness
7. 7
   기타Purification by column chromatography (silica gel, 300 g; n-hexane/ethyl acetate (17/3))

실험 절차

To a stirred solution of 2-methyl-1H-benzimidazole (6.61 g, 50 mmol) in dimethylacetamide (40 ml) at room temperature under a nitrogen atmosphere was added sodium hydride (2.40 g, 60 mmol) in portions during 15 min. At the point where the reaction mixture was too viscous to stir, the reaction was diluted with 100 ml of dimethylacetamide. After 50 min., a solution of 2-fluoropyridine (5.83 g, 60 mmol) in dimethylacetamide (30 ml) was added during 15 min. The resulting mixture was heated at 100° C. for 2 h and then to reflux for about 4 h. Volatiles were removed by evaporation under reduced pressure. The residue was dissolved into ethyl acetate (200 ml) and washed consecutively with water (3×100 ml) and brine (100 ml). The organic layer was dried (magnesium sulfate) and concentrated to dryness. Purification by column chromatography (silica gel, 300 g; n-hexane/ethyl acetate (17/3)) yielded 7.46 g (71%) of the titled compound as a light yellow liquid. 1H-NMR (CDCl3) δ: 8.72-8.67 (1H, m), 7.95 (1H, ddd, J=7.7, 7.7, 1.8 Hz), 7.78-7.74 (1H, m), 7.49-7.36 (3H, m), 7.32-7.20 (2H, m), 2.69 (3H, s).

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