Imidazole → 3-(2-Iodoethyl)-1-benzothiophene

To a stirred solution of 2-(1-benzothiophene-3-yl)ethanol (890 mg, 5 mmol) in anhydrous THF (50 ml), triphenylphosphine (1.572 g, 6 mmol), iodine (1.518 g, 6 mmol) and imidazole (408 mg, 6 mmol) were added at room temperature. The reaction mixture was stirred at room temperature for 4 hrs and quenched with water. It was extracted with chloroform, washed well with 5% Na2S2O3 solution and the organic layer was dried over anhydrous MgSO4. It was filtered and concentrated. The residue was purified by silica-gel column chromatography by eluting it with 30% ethyl acetate:hexane. The product, namely 2-(1-benzothiophene-3-yl)ethyl iodide, was obtained as brown liquid. Yield: 1.2 g (85%); 285 (M+H).