Into a 8-mL round-bottom flask purged and maintained with an inert atmosphere of nitrogen, was placed 6-[bis(4-chlorophenyl)methyl]-4-bromoquinolin-2-ol (150 mg, 0.33 mmol, 1.00 equip), 1-(ethanesulfonyl)piperidin-4-amine (94.12 mg, 0.49 mmol, 1.50 equip), Pd2(dba)3 (30 mg, 0.03 mmol, 0.10 equip), dppf (63.4 mg, 0.11 mmol, 0.35 equip), Cs2CO3 (266 mg, 0.82 mmol, 2.50 equip), and 1,4-dioxane (3 mL). The resulting solution was stirred overnight at 100° C. The reaction was then quenched by the addition of water (100 mL). The resulting solution was extracted with ethyl acetate (3×50 mL) and the organic layers combined and dried over anhydrous sodium sulfate. The solids were filtered out. The filtrate was concentrated under vacuum. The residue was applied onto a silica gel column with dichloromethane/methanol (20:1). The resulting residue was recrystallized from ethyl acetate:petroleum ether in the ratio of 1:10 to yield 6-[bis(4-chlorophenyl)methyl]-4-[[1-(ethanesulfonyl)piperidin-4-yl]amino]quinolin-2-ol as an off-white solid.
