Dimethyl Sulfoxide → 5,11-Dioctylindolo[3,2-b]carbazole

Participants

Reaction Steps

A freshly prepared 50% aqueous NaOH solution (4 mL) was added to a well-stirred mixture of 5,11-dihydridoindolo[3,2-b]carbazole, (0.513 g, 2 mmol), benzyltriethylammonium chloride (0.09 g, 0.4 mmol), 1-bromooctane (1.55 g, 8 mmol), and DMSO (20 mL) in a 100-mL flask under an argon atmosphere. The mixture was stirred at room temperature for 2.5 h and then heated to 65° C. and maintained at this temperature for 4 h. Subsequently the reaction mixture was cooled down to room temperature and poured into 200 mL methanol with stirring. The precipitated yellow solid was filtered off and washed with water, and 3 times each with N,N-dimethylformamide, methanol, and acetone. The yellow solid was purified by column chromatography on silica gel using hexane as eluent. Recrystallization from hexane yielded 0.867 g (90.1%) of 5,11-dioctylindolo[3,2-b]carbazole, (1), which was subject to train sublimation to obtain electrically pure material for OTFT fabrication. DSC showed two endotherms at 84° C. and 101° C. on heating. 1H NMR (CDCl3): δ 8.21 (d, J=7.6 Hz, 2H), 8.01 (s, 2H), 7.47 (dd, J1=7.0 Hz, J2=0.9 Hz, 2H), 7.41 (d, J=7.6 Hz, 2H), 7.21 (dd, J1=7.0 Hz, J2=0.9 Hz, 2H), 4.40 (t, J=7.3 Hz, 4H), 1.95 (pent, J=7.3 Hz, 4H), 1.25-1.50 (m, 20H), 0.86 (m, 6H); IR (NaCl): 3050, 2952, 2921, 2852, 1510, 1469, 1482, 1326, 737 cm−1.

Provenance & Evidence