반응 #9062

반응 방정식

(2-nitrophenyl)-terephthalamic acid methyl ester

acetic acid

→

methyl 4-(benzimidazol-2-yl)-benzoate

수율 86.0%

반응 조건

후처리

1. 1
   온도at reflux for 1 h
2. 2
   온도The mixture was cooled
3. 3
   workup.STIRRINGstirred at room temperature for 2 h
4. 4
   농축concentrated under reduced pressure
5. 5
   기타The residue was partitioned between saturated sodium bicarbonate (10 mL) and ethyl acetate (10 mL)
6. 6
   기타the phases separated
7. 7
   세척the organic layer washed with saturated NaHCO3 (10 mL)
8. 8
   추출The organic extract
9. 9
   건조was dried (MgSO4)
10. 10
    여과filtered
11. 11
    농축concentrated

실험 절차

To a solution of (2-nitrophenyl)-terephthalamic acid methyl ester (0.23 g, 0.76 mmol) in glacial acetic acid (2.5 mL) was added iron powder (<5 μm mesh, 0.12 g, 2.1 mmol) and the mixture stirred at reflux for 1 h. The mixture was cooled, stirred at room temperature for 2 h and concentrated under reduced pressure. The residue was partitioned between saturated sodium bicarbonate (10 mL) and ethyl acetate (10 mL), the phases separated and the organic layer washed with saturated NaHCO3 (10 mL). The organic extract was dried (MgSO4), filtered and concentrated to give cyclized methyl 4-(benzimidazol-2-yl)-benzoate (0.163 g, 86%). 1H NMR (CDCl3) δ 3.96 (s, 3H), 7.32 (m, 2H), 7.53 (br, 1H), 7.84 (br, 1H), 8.17 (m, 4H), 9.65 (br, 1H (NH)).

출처