To a cloudy mixture of 6-bromo-2,4-dichloro-3-phenylquinoline (290.5 mg, 0.823 mmol, Intermediate 1: step c) and 1-methyl-1H-imidazole-5-carbaldehyde (90.6 mg, 0.823 mmol) in THF (8 mL) under nitrogen at −78° C. was added n-BuLi (1.6 M in hexane, 0.643 mL, 1.03 mmol) dropwise. The resulting solution was stirred at −78° C. for 3 hours, then was warmed to 0° C. for 15 minutes before addition of saturated aqueous NH4Cl to quench. The mixture was diluted with water and was extracted three times with EtOAc. The organic phase was dried (Na2SO4), filtered, and concentrated. The residue was purified by flash column chromatography (silica gel, 0-6% MeOH-DCM) to afford the title compound as a white powder.
