O-Xylene → 1-(4-Bromophenyl)-2-phenyl-1H-benzimidazole

Participants

Reaction Steps

Suspending 2.1 g (5.7 mmol) of N-[2-(4-bromophenylamino)phenyl] benzamide obtained in the above step (2) into 30 milliliter of xylene, and adding 0.6 g (2.9 mmol) of p-toluenesulfonic acid 1 hydrate, the resultant solution was azeotropically dehydrated while refluxing with heating for 3 hours. After naturally cooling the reacted solution, ethyl acetate, dichloromethane and water were added to the reacted solution, followed by separating an insoluble substance by filtration. Extracting an organic layer from mother liquor, the organic layer was washed with water and a saturated solution of sodium chloride and then, dried with anhydrous sodium sulfate, followed by removing the solvent by distillation under reduced pressure. Refining the residue with silicagel column chromatography, 1.0 g of 1-(4-bromophenyl)-2-phenyl-1H-benzimidazole was obtained as white crystals with a slight pink color (yield: 52%).

Provenance & Evidence