D. Sahu et al. / Tetrahedron 67 (2011) 303e311
309
to ꢁ78 ꢂC. 2-Isopropoxy-4,4,5,5-tetramethyl-[1,3,2] dioxaborolane
(1.37 mL, 6.7 mmol) was rapidly injected into the solution by a sy-
ringe, and the resulting mixture was stirred at ꢁ78 ꢂC for 1 h, and
followed by reacting overnight at room temperature. The resulting
mixture was quenched with H2O and extracted with dichloro-
methane. The dichloromethane extracts were washed with satu-
rated brine and dried with MgSO4. The solvent was removed by
rotary evaporator and the product was further purified by column
chromatography (silica) using a mixture of hexane and dichloro-
methane (4:1) as an eluent to yield a white solid (0.72 g, 45%). Mp:
152.1, 147.0, 145.2, 141.8, 140.7, 139.5, 137.6, 135.6, 134.6, 132.9, 127.3,
125.7, 125.0, 124.7, 124.2, 124.0, 120.5, 120.0, 55.6, 40.6, 31.68, 29.9,
23.0, 22.8, 14.2. MS (FAB): m/z [Mþ] 883; calcd m/z [Mþ] 882.18.
4.2.10. (2E,20E)-3,30-(50,500-(9,9-Dihexyl-9H-fluorene-2,7-diyl)bis
(2,20-bithiophene-50,5-diyl))bis(2-cyanoacrylic acid) (S1). Acetic acid
(40 mL) was added to a flask containing a mixture of compound 10a
(400 mg, 0.56 mmol), ammonium acetate (170 mg, 2.25 mmol), and
cyanoacetic acid (236 mg, 2.35 mmol). The mixture was refluxed for
36 h and allowed to cool to room temperature. The resulting solid
was filtered and washed with excess of distilled water, followed by
dichloromethane to give a dark brown solid (390 mg, 82.4%). Mp:
147e149 ꢂC. 1H NMR (300 MHz, CDCl3),
d (ppm): 7.50 (s, 2H),
4.25e4.16(m, 1H), 2.08e1.86 (m, 2H), 1.86e1.76 (m, 2H), 1.37 (s,
24H),1.14 (m, 24H), 0.84 (t, J¼6.9 Hz, 6H). 13C NMR (75 MHz, CDCl3),
287e289 ꢂC. 1H NMR (300 MHz, DMSO-d6),
d (ppm): 8.49 (s, 2H),
d
(ppm): 147.8, 126.0, 120.7, 121.5, 84.3, 60.3, 35.2, 31.7, 31.5, 26.6,
7.98 (d, J¼4.5 Hz, 2H), 7.87e7.81 (m, 4H), 7.70 (dd, J¼3.3 Hz,
J¼9.9 Hz, 6H), 7.62 (d, J¼3.9 Hz, 2H), 2.06 (m, 4H), 1.03e0.96 (m,
12H), 0.66 (t, J¼6.3 Hz, 6H), 0.51 (m, 4H). 13C NMR (75 MHz, DMSO-
25.0, 22.6, 14.2. MS (FAB): m/z [Mþ] 670; calcd m/z [Mþ] 669.42.
4.2.6. 5,50-(4-(Heptadecan-9-yl)-4H-dithieno[3,2-b:20,30-d]pyrrole-
2,6-diyl) dithiophene-2-carbaldehyde (8a). Mixture of compounds 6
(0.3 g, 0.46 mmol), 7a (0.197 g, 1.03 mmol), and K2CO3 (0.161 g,
1.16 mmol) were dissolved in 20 mL of toluene/ethanol (3:1) and
degassed for 10 min, which was followed by the addition of 20 mg Pd
(PPh3)4 as a catalyst. The resulting mixture was stirred under reflux
for 36 h. The solvent was removed under vacuum and extracted with
dichloromethane and washed with water followed by a little brine.
The organic phase was dried with anhydrous MgSO4, and the solvent
was removed by rotary evaporator. Afterward, the crude compound
was purified by column chromatography (silica) using a mixture of
hexaneanddichloromethane(1:1)asaneluent. Theobtainedproduct
wasrecrystallized from ethanol toyieldanorangecolor solid (210 mg,
d6), d (ppm): 164.3, 152.3, 147.0, 146.6, 146.3, 142.3, 141.0, 134.6,
132.6, 129.1, 126.2, 125.6, 125.4, 121.5, 120.4, 117.3, 98.7, 55.8, 31.5,
29.5, 24.1, 22.6, 14.5. MS (FAB): m/z [Mþ] 853; calcd m/z [Mþ]
852.22. Anal. Calcd for C49H44N2O4S4: C, 68.98; H, 5.20; N, 3.28.
Found: C, 68.62; H, 5.49; N, 3.26.
4.2.11. 50,500-(9,9-Dihexyl-9H-fluorene-2,7-diyl)-di-[2,20:50,200-ter-
thiophene-500-(2-cyanoacrylic acid)] (S2). Compound S2 dye was
synthesized by the same procedure as S1, afforded dark brown solid
in 82.0% yield. Mp: 302e304 ꢂC. 1H NMR (300 MHz, DMSO-d6),
d
(ppm): 8.47 (s, 2H), 7.97 (d, J¼4.2 Hz, 2H), 7.83e7.76 (m, 4H),
7.63e7.58 (m, 8H), 7.49 (d, J¼3.6 Hz, 2H), 7.42 (d, J¼3.9 Hz, 2H), 2.06
(m, 4H), 1.00e0.95 (m, 12H), 0.65 (t, J¼6.3 Hz, 6H), 0.53 (m, 4H). 13C
70%). Mp: 128e130 ꢂC.1HNMR (300MHz,DMSO-d6),
d
(ppm): 9.85(s,
NMR (75 MHz, DMSO-d6), d (ppm): 164.3, 152.2, 146.9, 145.8, 144.6,
2H), 7.96 (d, J¼3.9 Hz, 2H), 7.91 (s, 2H), 7.53 (d, J¼3.9 Hz, 2H),
142.1, 140.7, 139.0, 135.1, 134.7, 134.2, 132.8, 128.8, 127.1, 126.1, 125.1,
125.0,121.3,120.1,117.2, 98.1, 55.1, 31.0, 29.1, 24.1, 22.1,14.4. MS (FAB):
m/z [Mþ] 1017; calcd m/z [Mþ] 1016.19. Anal. Calcd for C57H48N2O4S6:
C, 67.29; H, 4.76; N, 2.75. Found: C, 66.61; H, 5.02; N, 2.85.
4.49e4.44 (m, 1H), 2.06e2.03 (m, 2H), 1.83e1.79 (m, 2H), 1.06 (m,
24H), 0.71 (t, J¼6.9 Hz, 6H). 13C NMR (75 MHz, DMSO-d6),
d (ppm):
182.5,148.2,146.6,142.1,134.5,133.9,124.9, 59.6, 34.4, 31.7, 29.3, 29.0,
26.4, 22.6, 14.4. MS (FAB): m/z [Mþ] 638; calcd m/z [Mþ] 637.22.
4.2.12. (2E,20E)-3,30-(5,50-(4-(Heptadecan-9-yl)-4H-dithieno[3,2-
b:20,30-d]pyrrole-2,6-diyl)bis(thiophene-5,2-diyl))bis(2-cyanoacrylic
acid) (S3). Compound S3 dye was synthesized by the same pro-
cedure as S1, afforded dark brown solid in 89.6% yield. Mp:
4.2.7. 50,500-(4-(Heptadecan-9-yl)-4H-dithieno[3,2-b:20,30-d]pyrrole-
2,6-diyl)di-20,200-bithiophene-5-carbaldehyde (8b). Compound 8b
was synthesized by the same procedure as compound 8a, afforded
an orange solid in 69.5% yield. Mp: 135e137 ꢂC. 1H NMR (300 MHz,
281e283 ꢂC. 1H NMR (300 MHz, DMSO-d6),
d (ppm): 8.44 (s, 2H),
DMSO-d6),
d
(ppm): 9.86 (s, 2H), 7.98 (d, J¼3.9 Hz, 2H), 7.70 (s, 2H),
7.94 (d, J¼4.5 Hz, 2H), 7.90 (s, 2H), 7.58 (d, J¼3.9 Hz, 2H), 4.49 (m,
7.55 (d, J¼3.9 Hz, 2H), 7.51 (d, J¼3.9 Hz, 2H), 7.35 (d, J¼3.9 Hz, 2H),
1H), 2.07e2.03 (m, 2H), 1.78e1.74 (m, 2H), 1.04 (m, 24H) 0.71 (t,
4.44 (m, 1H), 2.03 (m, 2H), 1.80 (m, 2H), 1.13e0.95 (m, 24H), 0.72 (t,
J¼6.9 Hz, 6H). 13C NMR (75 MHz, DMSO-d6),
d (ppm) 164.5, 148.4,
J¼6.9 Hz, 6H). 13C NMR (75 MHz, DMSO-d6),
d
(ppm): 182.7, 146.6,
146.8, 142.3, 134.6, 134.1, 125.0, 117.4, 116.7, 112.4, 97.9, 59.8, 34.5,
31.9, 29.4, 29.2, 26.5, 22.7, 14.5. MS (FAB): m/z [Mþ] 772; calcd m/z
[Mþ] 771.23. Anal. Calcd for C41H45N3O4S4: C, 63.78; H, 5.87; N,
5.44. Found: C, 63.34; H, 5.80; N, 5.30.
146.0, 142.1, 140.0, 134.2, 133.3, 128.7, 125.1, 59.8, 34.4, 31.8, 29.4,
29.2, 26.4, 22.6,14.4. MS (FAB): m/z [Mþ] 802; calcd m/z [Mþ] 801.19.
4.2.8. 50,500-(9,9-Dihexyl-9H-fluorene-2,7-diyl)di-2,20-bithiophene-
50-carbaldehyde (10a). Compound 10a was synthesized by the same
procedure as compound 8a, afforded a yellow solid in 78.2% yield.
4.2.13. (2E,20E)-3,30-(50,500-(4-(Heptadecan-9-yl)-4H-dithieno[3,2-
b:20,30-d]pyrrole-2,6-diyl)bis(20,200-bithiophene-50,50-diyl))bis(2-cya-
noacrylic acid) (S4). Compound S4 dye was synthesized by the same
procedure as S1, afforded dark brown solid in 88.2% yield. Mp:
Mp: 143e145 ꢂC. 1H NMR (300 MHz, CDCl3),
d (ppm): 9.89 (s, 2H),
7.73e7.69 (m, 4H), 7.62 (dd, J¼1.5, 7.8 Hz, 2H), 7.56 (s, 2H), 7.39e7.35
(m, 4H), 7.30 (d, J¼3.9 Hz, 2H), 2.07e2.01(m, 4H),1.14e1.06 (m,12H),
0.75 (t, J¼6.6 Hz, 6H), 0.69 (m, 4H). 13C NMR (75 MHz, CDCl3),
292e294 ꢂC. 1H NMR (300 MHz, DMSO-d6),
d (ppm): 8.42 (s, 2H),
7.92 (d, J¼4.2 Hz, 2H), 7.68 (s, 2H), 7.51e7.46 (m, 4H), 7.29 (d,
d
(ppm): 182.6, 152.21, 147.4, 147.0, 141.76, 140.0, 137.6, 135.1, 132.8,
J¼3.6 Hz, 2H), 4.39 (m, 1H), 2.01 (m, 2H), 1.75 (m, 2H), 1.11e0.91 (m,
127.4, 125.2, 124.3, 124.2, 120.7, 120.2, 55.6, 40.6, 31.7, 29.85, 23.0,
24H) 0.70 (t, J¼6.6 Hz, 6H). 13C NMR (75 MHz, DMSO-d6),
d (ppm):
22.8, 14.2. MS (FAB): m/z [Mþ] 719; calcd m/z [Mþ] 718.21.
164.3,146.8,146.1,142.3,140.9,134.4,134.2,133.4,128.8,125.3,117.3,
110.8, 98.5, 59.9, 34.6, 31.9, 29.5, 29.2, 26.5, 22.7, 14.5. MS (FAB): m/z
[Mþ] 935; calcd m/z [Mþ] 935.20. Anal. Calcd for C49H49N3O4S6: C,
62.85; H, 5.27; N, 4.49. Found: C, 62.62; H, 5.58; N, 4.78.
4.2.9. 50,500-(9,9-Dihexyl-9H-fluorene-2,7-diyl)-di-2,20:50,200-terthio-
phene-500-carbaldehyde (10b). Compound 10b was synthesized by
the same procedure as compound 8a, afforded a reddishyellowsolid
in 75.0% yield. Mp: 184e186 ꢂC. 1H NMR (300 MHz, CDCl3),
d
(ppm):
4.3. Measurement and characterizations
9.87 (s, 2H), 7.71e7.68 (m, 4H), 7.60 (dd, J¼1.8, 8.1 Hz, 2H), 7.56 (s,
2H), 7.33 (d, J¼3.9 Hz, 2H), 7.31 (d, J¼3.9 Hz, 2H) 7.26e7.23 (m, 4H),
7.18 (d, J¼3.9 Hz, 2H), 2.06e2.01(m, 4H), 1.15e1.07 (m, 12H), 0.76 (t,
1H NMR spectra were recorded on a Varian unity 300 MHz
spectrometer using DMSO-d6 and CHCl3-d as solvents. Elemental
analyses were performed on a HERAEUS CHN-OS RAPID elemental
J¼6.6 Hz, 6H), 0.69 (m, 4H).13C NMR (75 MHz, CDCl3),
d (ppm): 182.6,