ALIQUAT™ 336 (0.6 g), 2-thiopheneboronic acid (0.921 g, 7.2 mmol), 2,8-dibromo-5,11-didodecylindolo[3,2-b]carbazole (2.252 g, 3 mmol), 2M Na2CO3 solution (7.5 mL, 15 mmol), Pd(PPh3)4 (72 mg, 0.06 mmol) and toluene (10 mL) were added into a 50 mL flask. The mixture was heated to gentle reflux and maintained for 48 h. The reaction mixture was cooled down, organic layer separated, dried, and filtered. The toluene solution was passed through a silica gel column and the solvent was removed. Recrystallization from toluene gave the title compound as a yellow solid. Yield: 1.476 g (61%).
