To a 125 mL three-necked round-bottomed flask equipped with septum and N2 inlet were added 2.93 g (8.88 mmol) N-benzyl-4-(4-bromophenyl)piperidine and 30 mL dry ether. The solution was cooled to −70° C., and 6.66 mL (10.65 mmol) of a 1.6 N solution of butyl lithium in hexane added dropwise over 5 minutes. After stirring a further 5 minutes at −70° C., the solution was warmed slowly to room temperature over 25 minutes. A solution of 1.83 g (10.65 mmol) 2-(2,5-dimethylpyrrolyl)pyridine in 10 mL dry ether was then added dropwise over 5 minutes, and the reaction, which turned slowly dark red, stirred at room temperature for 3 hours. The reaction was quenched with aqueous ammonium chloride solution, partitioned between ethyl acetate and water, and the organic layer separated, washed with brine, and dried over sodium sulfate, allowing it to stand overnight to effect rearomatization of the pyridine ring. After evaporation of the solvent, the residue was chromatographed on silica gel using ethyl acetate/hexane followed by methanol/methylene chloride as eluant to afford 1.21 g (32%) of an oil.
