Methyl 4′-(4-bromo-5-chloropyridin-2-ylamino)-5′-methoxy-2′-methylbiphenyl-4-carboxylate generated in Step 2 (9 mg, 0.022 mmol), 2-(isopropylsulfonyl)aniline (4 mg, 0.022 mmol, 1 equiv), Pd2(dba)3 (1.7 mg, 0.002 mmol, 0.1 equiv.), 2-(Dicyclohexylphosphino)-2′,4′,6′-tri-1-propyl-1,1′-biphenyl (1.8 mg, 0.004 mmol, 0.2 equiv.), and Sodium tert-butoxide (2.7 mg, 0.028 mmol, 1.3 equiv.) are added to THF (1 mL). The resulting mixture is bubbled with N2 gas for 5 minutes and then heated at 150° C. for 4 hours. After cooling to room temperature, the reaction mixture is diluted into EtOAc and washed with H2O. The EtOAc layer is dried over Mg2SO4 and concentrated in vacuo. Silica gel chromatography (hexanes-EtOAc) affords Methyl 4′-(5-chloro-4-(2-(isopropylsulfonyl)phenylamino)pyridin-2-ylamino)-5′-methoxy-2′-methylbiphenyl-4-carboxylate (254); MS m/z 580.2 (M+1).
