Reaktion #79145

Reaktionsgleichung

(E)-cinnamoyl chloride

N-(3-pyridyl)-o-phenylenediamine

→

brown solids

Ausbeute 34.0%

(E)-1-(3-Pyridyl)-2-styryl-1H-benzimidazole

Ausbeute 34.0%

Lösungsmittel

xylene

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe resulting mixture was heated
2. 2
   Temperaturto reflux
3. 3
   Sonstigeremoving water using a Dean-Stark apparatus for 11 h
4. 4
   TemperaturAfter cooling
5. 5
   Einengenthe reaction mixture was concentrated to dryness
6. 6
   workup.DISSOLUTIONThe residue was dissolved into ethyl acetate (100 ml)
7. 7
   Waschenwashed consecutively with saturated aqueous sodium bicarbonate solution (50 ml) and brine (50 ml)
8. 8
   Trocknendried (magnesium sulfate)
9. 9
   Einengenconcentrated to dryness
10. 10
    SonstigeThe residue was purified by column chromatography (silica gel, 165 g; n-hexane/ethyl acetate (3/2 to 1/1))

Vorschrift

To a stirred suspension of N-(3-pyridyl)-o-phenylenediamine (0.93 g, 5 mmol; Kirsch, P.; Schoenleben-Janas, A.; Schirmer, R. H. Liebigs Ann. Org. Bioorg. Chem., 1995, 7, 1275) in xylene (60 ml) was added (E)-cinnamoyl chloride (0.83 g, 5 mmol). After stirring at the room temperature for 1h, the resulting mixture was heated to reflux removing water using a Dean-Stark apparatus for 11 h. After cooling, the reaction mixture was concentrated to dryness. The residue was dissolved into ethyl acetate (100 ml), washed consecutively with saturated aqueous sodium bicarbonate solution (50 ml) and brine (50 ml), dried (magnesium sulfate) and concentrated to dryness. The residue was purified by column chromatography (silica gel, 165 g; n-hexane/ethyl acetate (3/2 to 1/1)) to give 0.77 g (34%) of brown solids. Recrystallization from isopropyl ether yielded 0.50 g of the titled compound as pink solids. MW: 297.36; mp: 118.0-118.5° C.; 1H-NMR (CDCl3) δ: 8.84 (1H, dd, J=4.8, 1.5 Hz), 8.79 (1H, d, J=2.6 Hz), 8.00 (1H, d, J=15.8 Hz), 7.88-7.79 (2H, m), 7.61 (1H dd, J=8.1, 4.8 Hz), 7.50-7.44 (2H, m), 7.39-7.15 (6H, m), 6.78 (1H, d, J=15.8 Hz).

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