A solution of 4-bromo-7-(1-ethylpropyl)-1-methyl-1,3-dihydro-2H-benzimidazol-2-one (250 mg, 0.84 mmol), tetrakis(triphenylphosphine)palladium (194 mg, 0.168 mmol), tetramethyltin (1.16 mL, 8.4 mmol) in hexamethylphosphoric triamide (5 mL) was refluxed for 18 h. After cooling, the mixture was diluted with water and extracted with dichloromethane. The organics were dried over magnesium sulfate, filtered and concentrated in vacuo. The residue was purified by column chromatography on a silica gel (n-hexane/ethyl acetate=90:10-50:50) to give the title compound (111 mg, 0.48 mmol, 57%).
