1,3-Propanediol → 1-Phenyl-7-(4-pyridyl)-5-trifluoromethylbenzimidazole

Participants

Reaction Steps

A mixture of 7-iodo-1-phenyl-5-trifluoromethylbenzimidazole (3.0 g, 7.5 mmol), pyridine 4-boronic acid (1.38 g, 11.2 mmol), 1,3-propanediol (2.7 ml, 37.3 mmol), potassium carbonate (5.2 g, 37.3 mmol) and bis(triphenylphosphin)palladium dichloride (200 mg, 0.28 mmol) in a mixture of dimethoxyethane (30 ml) and water (15 ml) was stirred at reflux for 5 days. The cooled reaction mixture was concentrated under reduced pressure, and the concentrate was partitioned between water and ethyl acetate. The organic phase was dried and concentrated under reduced pressure, and the concentrate was purified by column chromatography on silica gel eluting with a mixture of ligroin and ethyl acetate (1:1 v/v). The product was isolated as a yellowish solid by evaporation of solvent from the eluate (1.55 g, 61%) m/z, 340.1 (M+H)+.

Provenance & Evidence