Butyllithium (0.5 mL of 2.5M in hexanes) was added to a cooled (-78° C.) solution of 2,6,7-trimethyl-1-(2-methylpropyl)-N4,N4 -bis(phenylmethyl)-1H-imidazo[4,5-c]pyridin-4-amine (0.5 g, 1.2 mmole) in tetrahydrofuran (30 mL). The reaction mixture was allowed to warm to -10° C. then it was cooled to -78° C. and combined with methyl iodide (0.23 mL, 3.6 mole). The reaction mixture was allowed to warm to ambient temperature then diluted with water and diethyl ether. The ether layer was separated, washed with ammonium chloride solution, dried over magnesium sulfate and then concentrated to provide 0.5 g of the desired product.
