Reaction Steps
A mixture of Intermediate E (90%, 488 mg, 0.50 mmol),), benzo[b]thiophen-2-ylboronic acid (356 mg, 2.00 mmol), sodium carbonate (530 mg, 5 mmol) in water (4 mL), tetrakis(triphenylphosphine)palladium (0) (240 mg, 0.20 mmol), n-butanol (15 mL), and toluene (15 mL) was heated under argon at 110° C. for 24 hours. The reaction mixture was poured into water (200 mL), treated with 5N NaOH (25 mL), stirred for 1 hour, and extracted with dichloromethane (3×200 mL). The volatiles were removed under reduced pressure, and the residue was chromatographed (silica gel, dichloromethane/tetrahydrofuran 9:1). The obtained product was washed with ethyl acetate and dried in a vacuum oven to give 2,7-bis(7-(benzo[b]thiophen-2-yl)-2-(pyridin-4-yl)-2H-benzo[d][1,2,3]triazol-4-yl)-9,9-dihexyl-9H-fluorene (Example 24), orange crystals, 430 mg (87%). 1H NMR (400 MHz, CDCl3): δ 8.89 (m, 4H, pyridine), 8.56 (s, 2H, benzothiophene), 8.44 (m, 4H, pyridine), 8.21 (s, 2H, fluorene), 8.14 (d, 2H, J=8.8 Hz, fluorene), 7.88-7.98 (m, 8H, benzothiophene, fluorene and benzotriazole), 7.79 (d, J=7.3 Hz, 2H, benzotriazole), 7.41 (m, 4H, benzothiophene), 2.20 (m, 4H, hexyl), 1.20 (m, 4H, hexyl), 1.14 (m, 8H, hexyl), 0.95 (m, 4H, hexyl), 0.74 (t, J=6.5 Hz, 6H, hexyl). UV-vis spectrum (dichloromethane): λmax=440 nm. Fluorimetry (dichloromethane): λmax=515 nm.
