Br[C:2]1[S:3][C:4](Br)=[CH:5][C:6]=1[Br:7].[CH3:9][O:10][C:11]1[CH:16]=[CH:15][C:14](B(O)O)=[CH:13][CH:12]=1.[C:20](=[O:23])([O-])[O-].[Na+].[Na+].C(Cl)(Cl)Cl>C1COCC1.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.CCOC(C)=O>[Br:7][C:6]1[CH:5]=[C:4]([C:14]2[CH:15]=[CH:16][C:11]([O:10][CH3:9])=[CH:12][CH:13]=2)[S:3][C:2]=1[C:11]1[CH:16]=[CH:15][C:14]([O:23][CH3:20])=[CH:13][CH:12]=12,3,5-Tribromothiophene (6.42 g, 20 mmol), 4-methoxyphenylboronic acid (6.38 g, 42 mmol) and sodium carbonate (8.5 g, 80 mmol) were stirred in THF/water mixture (125/50 ml) for 90 min at RT under argon flushing. Pd(PPh3)4 (693 mg, 0.6 mmol) was added. The mixture was refluxed for 16 h (TLC), cooled to RT and THF was removed by evaporation. Water was added and aqueous fractions extracted with EtOAc. The organic fractions were combined, solvent removed and the crude product purified by flash chromatography (Silica gel; hexane/chloroform/EtOAc; gradient up to 20% chloroform then 20% EtOAc) to yield 3-bromo-2,5-bis(4-methoxyphenyl)thiophene (4.9 g, 13 mmol, 65%).
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