To a mixture of 4-octyloxy-phenylboronic acid (Compound 7) (12.0 g, 0.048 mol), 5,5′-dibromo-2,2′-bithiophene (Compound 8) (7.23 g, 0.022 mol), bis(triphenylphosphine) palladium (II) dichloride (0.39 g, 0.56 mmol), and potassium phosphate (15.3 g, 0.072 mol), 160 mL ethylene glycol dimethylether and 50 mL water were added. After heating for 4 hours at 70° C., the reaction mixture was cooled on an ice bath. The solids were filtered and washed with a small amount of chloroform. The solids were suspended in 600 mL water, stirred for 30 minutes, and then filtered. This washing procedure was repeated with methanol. Following two crystallizations from trifluorotoluene using decolorizing charcoal, 5,5′-di(4-octyloxy-phenyl)-2,2′-bithiophene (Compound 4) was isolated as yellow/orange crystals (10.34 g, 81%).
