To a stirred solution of 1-bromo-6,7-dimethoxy-isoquinoline-4-carbonitrile (100 mg, 0.34 mmol), 3-methylsulfanyl-benzaldehyde (104 g, 0.68 mmol) and 1,3-dimethyl-1H-imidazolium iodide (153 mg, 0.68 mmol) in N,N-dimethylformamide (3 mL) was added sodium hydride (27.3 mg, 0.68 mmol). The mixture turned black instantly. The reaction mixture was stirred at room temperature for 1 h. Water was added and the aqueous phase was extracted with dichloromethane (3×20 mL). The combined extracts were washed with saturated sodium chloride solution (20 mL), dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 70–230 mesh, 20% ethyl acetate/hexane) afforded 6,7-dimethoxy-1-(3-methylsulfanyl-benzoyl)-isoquinoline-4-carbonitrile (70 mg, 57% yield) as a colorless oil.
