Br[C:2]1[C:10]2[C:6](=[CH:7][N:8]([CH3:11])[N:9]=2)[CH:5]=[CH:4][CH:3]=1.[CH3:12][O:13][C:14]1[CH:19]=[CH:18][C:17](B(O)O)=[C:16]([CH3:23])[CH:15]=1.C(=O)([O-])[O-].[Na+].[Na+]>COCCOC.O.CCOC(C)=O.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[CH3:12][O:13][C:14]1[CH:19]=[CH:18][C:17]([C:2]2[C:10]3[C:6](=[CH:7][N:8]([CH3:11])[N:9]=3)[CH:5]=[CH:4][CH:3]=2)=[C:16]([CH3:23])[CH:15]=17-Bromo-2-methyl-2H-indazole (4; 1.76 g, 8.3 mMol) and tetrakis(triphenylphosphine)palladium(0) (0.28 g, 0.25 mMol) were stirred in 15 mL of DME under argon atmosphere for 30 min. 4-Methoxy-2-methylbenzeneboronic acid (1.52 g, 9.2 mMol) was added, immediately followed by a solution of sodium carbonate (3.1 g, 29.1 mMol) in 10 mL water. The mixture was heated at a gentle reflux for 4 hr, and then cooled to rt and diluted with EtOAc (150 mL). The organic phase was washed with brine and dried over magnesium sulfate. Evaporation of the solvent afforded an oil, which was flash chromatographed on SiO2 and eluted with hexane:EtOAc (9:1) to afford 4c (1.9 g; 91%).
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