反应详情

According to the literature procedure (Trecourt, F.; Mallet, M.; Mongin, O,.; Queguiner, G. J. Org. Chem. 1994, 59, 6173.), a solution of (E)-1-(6-Chloropyridin-2-yl)-2-styryl-1H-benzimidazole (145 mg, 0.44 mmol), 28% NaOEt in MeOH (3 ml) and toluene (5 ml) was maintained at room temperature for 2 h then heated under reflux condition for 1 h. To this solution, water (1 ml) was added and it was concentrated by evaporator. To this residue , water (5 ml) was added and the whole was extracted with CH2Cl2 (2×15 ml). Combined organic layer was dried (magnesium sulfate) and filtered. The filtrate was concentrated and the residue was purified by column chromatography (silica gel, 20 g; n-hexane/ethyl acetate (5/1)) to afford the desired compound (35 mg, 24%). The free base was treated with a 10% methanol solution of hydrogen chloride and concentrated to dryness. The residue was recrystallized from ethyl acetate/n-hexane to give the titled compound. MW: 363.85; mp: 199.0-200.0° C.; 1H-NMR (DMSO) δ: 8.15-8.08 (2H, m), 7.85 (1H, d, J=8.1 Hz), 7.74-7.66 (3H, m), 7.56-7.20 (6H, m), 7.15 (1H, d, J=8.4 Hz), 702-7.00 (1H, m), 3.90 (3H, s).

1. temperaturethen heated
2. temperatureunder reflux condition for 1 h
3. concentrationit was concentrated by evaporator
4. additionTo this residue , water (5 ml) was added
5. extractionthe whole was extracted with CH2Cl2 (2×15 ml)
6. dry with materialCombined organic layer was dried (magnesium sulfate)
7. filtrationfiltered
8. concentrationThe filtrate was concentrated
9. customthe residue was purified by column chromatography (silica gel, 20 g; n-hexane/ethyl acetate (5/1))