[Br:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]([F:11])([F:10])[F:9])=[CH:4][C:3]=1I.[N:13]1[CH:18]=[CH:17][C:16](B(O)O)=[CH:15][CH:14]=1.C(=O)(O)[O-].[Na+]>C(COC)OC.O.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.Cl[Pd]Cl.[Fe+2]>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]([F:11])([F:10])[F:9])=[CH:4][C:3]=1[C:16]1[CH:17]=[CH:18][N:13]=[CH:14][CH:15]=1To a solution of compound 1-bromo-2-iodo-4-(trifluoromethyl)benzene (10 g, 28.4 mmol) and pyridin-4-ylboronic acid (7 g, 34.1 mmol) in dimethoxyethane (150 mL) and water (50 mL), sodium bicarbonate (9.54 g, 113.6 mmol) was added. The reaction mixture was purged with nitrogen for 15 minutes and Pd(dppf)2Cl2 (2.3 g, 2.84 mmol) was added. The reaction was stirred at 90° C. for 5 h. Then the reaction mixture was diluted with water (500 mL) extracted with ethyl acetate (2×200 mL). Organic layer was combined, dried over sodium sulfate, filtered and concentrated under a vacuum to give the compound which was further purified by column chromatography using silica gel (100 to 200 mesh) and 0% to 30% ethyl acetate/hexane as eluent to obtain 4-(2-bromo-5-(trifluoromethyl)phenyl)pyridine (6.7 g, 77.6%) as an off white solid. MS (ESI, positive ion) [M+1]+: 301.98; 1H NMR (400 MHz, DMSO) δ 8.71 (d, J=5.9 Hz, 2H), 8.05 (d, J=8.2 Hz, 1H), 7.84-7.75 (d, J=11.3 Hz, 2H), 7.50 (d, J=5.9 Hz, 2H).
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