Réaction #79145

Équation de réaction

(E)-cinnamoyl chloride

N-(3-pyridyl)-o-phenylenediamine

→

brown solids

Rendement 34.0%

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

Rendement 34.0%

Solvants

xylene

Conditions de réaction

Traitement

1. 1
   Températurethe resulting mixture was heated
2. 2
   Températureto reflux
3. 3
   Autreremoving water using a Dean-Stark apparatus for 11 h
4. 4
   TempératureAfter cooling
5. 5
   Concentrationthe reaction mixture was concentrated to dryness
6. 6
   workup.DISSOLUTIONThe residue was dissolved into ethyl acetate (100 ml)
7. 7
   Lavagewashed consecutively with saturated aqueous sodium bicarbonate solution (50 ml) and brine (50 ml)
8. 8
   Séchagedried (magnesium sulfate)
9. 9
   Concentrationconcentrated to dryness
10. 10
    AutreThe residue was purified by column chromatography (silica gel, 165 g; n-hexane/ethyl acetate (3/2 to 1/1))

Mode opératoire

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).

Source