Synthesis and characterization of 9,9-dialkylfluorene capped benzo[c]thiophene/benzo[c]selenophene analogs as potential OLEDs

Synthesis and characterization of fluorene tethered benzo[c]thiophene/benzo[c]selenophene analogs

“…28 Thus, the exciting photophysical properties along with enormous application potential of benzo[c]thiophenes prompted us to explore the synthesis and characterization of various types of symmetrical as well as unsymmetrical 1,3-diarylbenzo[c]thiophenes. 29 In continuation of the preliminary report on synthesis of fluorene capped benzo[c]thiophenes 30 and dibenzoheterocycle tethered benzo[c] thiophenes 2e4, 29e we reported herein a detailed study on synthesis and characterization of 9,9-disubstituted fluorenyl benzo[c] thiophenes.…”

“…Following the above-mentioned procedure (A), keto-acid 11b was obtained using 2,7-bis(2-thienyl)-9,9-dihexyl fluorene 10b (5 g, 10.00 mmol), phthalic anhydride (1.78 g, 12.02 mmol), and AlCl 3 (2.40 g, 18.02 mmol) as a thick yellow liquid (3. 30 …”

“…Following the above-mentioned procedure (B), benzo[c]thiophene 9n was obtained using the lactone 8b (0.7 g, 1.50 mmol), 1-naphthalenylmagnesiumbromide [prepared from 1-bromonaphthalene (0.62 g, 3.00 mmol) and Mg (0.08 g, 3.61 mmol)], and Lawesson's reagent (0. 30 5.3.20. 1-(5-(9,9-Dihexyl-9H-fluoren-2-yl)thiophen-2-yl)-3-(5-hexylthiophen-2-yl)benzo[c]thiophene (13c).…”

“…5.3.8. 1-(9,9-Dihexyl-9H-fluoren-2-yl)-3-(thiophen-2-yl)benzo[c]-thiophene (9h).Following the above-mentioned procedure (B), benzo[c]thiophene 9h was obtained using the lactone 8b (0.7 g, 1.50 mmol), 2-thienylmagnesium bromide [prepared from 2-bromothiophene (0.49 g, 3.00 mmol) and Mg (0.08 g, 3.61 mmol)], and Lawesson's reagent (0 30. g, 0.74 mmol) as a thick orange liquid (0.51 g, 62%); [found: C, 80.8; H, 7.3; S, 11.9.…”

“…1-(9,9-Dihexyl-9H-fluoren-2-yl)-3-(3-hexylthiophen-2-yl) benzo[c]thiophene (9i). Following the above-mentioned procedure (B), benzo[c]thiophene 9i was obtained using the lactone 8b (0.7 g, 1.50 mmol), 3-hexyl-2-thienyl magnesiumbromide [prepared from 2-bromo-3-hexylthiophene (0.74 g, 3.00 mmol) and Mg (0.08 g, 3.61 mmol)], and Lawesson's reagent (0 30. g, 0.74 mmol) as a thick orange liquid (0.54 g, 57%); [found: 20e1.15 (12H, m, CH 2 CH 3 ), 0.90e0.80 (13H, m, CH 2 CH 3 ); d C (75.6 MHz, CDCl 3 ) 151.61, 151.10, 146.10, 142.00, 141.00, 140.61, 136.60, 134.81, 132.85, 130.63, 129.22, 128.70, 127.30, 127.00, 125.90, 124.01, 123.80, 123.77, 123.00, 122.44, 121.60, 120.20, 119.90, 55.27, 40.40, 31.65, 31.50, 30.80, 29.73, 29.14, 29.10, 23.90, 22.61, 14.10, 14.05; MS (EI): m/z (%)¼632 [M] þ .…”