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2H), 4.32 (t, J = 7.2 Hz, 2H), 3.01 (t, J = 7.8 Hz, 2H), 2.90 (t, J =
7.6 Hz, 2H), 1.94–1.88 (m, 2H), 1.86–1.79 (m, 4H), 1.44–1.25
(m, 22H), 0.91–0.84 (m, 9H).
5-(4,49-dihexyl-59-(4-p-tolyl-1,2,3,3a,4,8b-hexahydrocyclo-
penta[b]indol-7-yl)-2,29-bithiazol-5-yl)thiophene-2-carbalde-
hyde (4). The synthesis method resembles that of compound 2
synthesis method resembles that of BTT-I using compound 3
reaction with 2-cyanoacetic acid, and the compound was
purified by column chromatography on silica gel (CH2Cl2/
1
EtOH = 20/1, v/v) to yield red solid (133 mg, yield 82.6%). H
NMR (THF-d8, 400 MHz), d: 8.54 (s, 1H), 8.04 (d, J = 4.0 Hz,
1H), 7.62 (d, J = 3.2 Hz, 1H), 7.43 (d, J = 8.0 Hz, 2H), 7.36 (t, J =
8.0 Hz, 4H), 7.15–7.10 (m, 6H), 7.01 (d, J = 8.0 Hz, 2H), 2.98 (t, J
= 7.4 Hz, 2H), 2.80 (t, J = 7.4 Hz, 2H), 1.78–1.65 (m, 4H), 1.30–
1.23 (m, 12H), 0.85 (t, J = 6.8 Hz, 6H). 13C NMR (THF-d8, 100
MHz), 165.1, 162.0, 159.0, 158.7, 156.0, 150.6, 149.7, 147.5,
144.2, 140.6, 138.8, 137.6, 132.2, 131.6, 130.2, 128.6, 127.3,
126.9, 125.9, 124.6, 118.1, 117.9, 34.2, 34.0, 33.0, 32.0, 31.9,
31.8, 31.4, 30.4, 29.4, 27.9, 27.8, 24.9, 23.8, 15.8. HRMS (m/z):
[M + H]+ Calcd for C44H45N4O2S3, 757.2705; Found, 757.2714.
2-Cyano-3-(5-(4,49-dihexyl-59-(4-p-tolyl-1,2,3,3a,4,8b-hexa-
hydrocyclopenta[b]indol-7-yl)-2,29-bithiazol-5-yl)thiophen-2-
yl)acrylic acid (BTT-III). The synthesis method resembles that
of BTT-I using compound 4 reaction with 2-cyanoacetic acid,
and the compound was purified by column chromatography on
silica gel (CH2Cl2/EtOH = 20/1, v/v) to give a dark red solid (110
mg, yield: 85%) 1H NMR (THF-d8, 400 MHz), d: 8.34 (s, 1H), 7.65
(d, J = 4.0 Hz, 1H), 7.32 (s, 1H), 7.25 (d, J = 8.4 Hz, 1H), 7.16–7.06
(m, 3H), 7.04 (d, J = 8.4 Hz, 2H), 6.85 (d, J = 8.0 Hz, 1H), 4.78 (t, J
= 6.6 Hz, 1H), 4.15 (t, J = 7.0 Hz, 1H), 3.82 (t, J = 8.8 Hz, 1H), 3.01–
2.92 (m, 6H), 2.21 (s, 3H), 2.04–1.97 (m, 1H), 1.77–1.71 (m, 4H),
1.56–1.53 (m, 1H), 1.37–1.24 (m, 13H), 0.86 (t, J = 6.8 Hz, 6H).
13C NMR (THF-d8, 100 MHz), 159.7, 156.0, 155.7, 152.7, 148.3,
140.0, 137.8, 137.7, 136.6, 135.6, 131.5, 129.9, 129.6, 128.5,
127.6, 127.5, 126.0, 125.4, 120.8, 120.3, 116.1, 107.0, 69.1, 67.7,
53.9, 45.2, 35.1, 33.4, 31.7, 30.8, 29.6, 29.5, 29.1, 29.0, 27.0, 22.6,
22.5, 22.0, 19.9, 13.5. HRMS (m/z): [M + H]+ Calcd for
C44H49N4O2S3 761.3018, Found: 761.3014.
using
4-p-tolyl-1,2,3,3a,4,8b-hexahydrocyclopenta[b]indol-7-
ylboronic acid reaction with compound 1, and the compound
was purified by column chromatography on silica gel (PE/
1
CH2Cl2 = 1/1, v/v) to give a red solid (150 mg, yield: 91%) H
NMR(CDCl3, 400 MHz), d (ppm): 9.91 (s, 1H), 7.73 (d, J = 4.0
Hz, 1H), 7.26 (d, J = 4.0 Hz, 1H), 7.22–7.16 (m, 5H), 7.12 (dd, J =
8.0 Hz, J = 1.2 Hz, 1H), 6.89 (d, J = 8.4 Hz, 1H), 4.84 (t, J = 6.6
Hz, 1H), 3.85 (t, J = 7.2 Hz, 1H), 3.74 (t, J = 6.2 Hz, 1H), 2.99 (t, J
= 7.8 Hz, 2H), 2.83 (t, J = 8.0 Hz, 2H), 2.34 (s, 3H), 2.12–2.03 (m,
1H), 1.95–1.87 (m, 2H), 1.83–1.76 (m, 4H), 1.63–1.59 (m, 1H),
1.45–1.29 (m, 13H), 0.91–0.86 (m, 6H).
2-cyano-3-(5-(4,49-dihexyl-59-(9-octyl-9H-carbazol-3-yl)-
2,29-bithiazol-5-yl)thiophen-2-yl)acrylic acid (BTT-I).
Compound 2 (100 mg, 0.138 mmol), 2-cyanoacetic acid (83
mg, 0.98 mmol) and ammonium acetate (200 mg) in acetic
acid (8 mL) at reflux for 6 h. After cooling the solution, the
mixture was poured into water to quench the reaction. The
precipitate was filtered and washed with water. The residue
was purified by column chromatography on silica gel (CH2Cl2
to CH2Cl2/EtOH = 20/1, v/v) to yield 83 mg of dark red solid
(yield 75.4%). 1H NMR (THF-d8, 400 MHz), d (ppm): 8.32 (s,
1H), 8.21 (d, J = 7.6 Hz, 1H), 7.80 (s, 1H), 7.69–7.63 (m, 2H),
7.56–7.48 (m, 4H), 7.23 (t, J = 7.2 Hz, 1H), 4.41 (t, J = 6.0 Hz,
2H), 2.96 (t, J = 7.4 Hz, 2H), 2.85 (t, J = 7.0 Hz, 2H), 1.76–1.71
(m, 6H), 1.30–1.17(m, 22H), 0.86–0.78(m, 9H).13C NMR(THF-
d8, 100 MHz), 165.2, 162.2, 161.7, 158.9, 146.5, 145.8, 143.4,
142.2, 142.1, 133.2, 131.7, 131.5, 128.8, 128.0, 127.2, 126.6,
126.4, 125.8, 125.7, 124.6, 114.6, 114.5, 84.2, 83.8, 83.5, 59.4,
48.2, 37.3, 37.2, 36.3, 35.2, 35.0, 34.9, 34.8, 34.7, 34.6, 34.5,
32.7, 28.1, 19.0. HRMS (m/z): [M + H]+ Calcd for C46H55N4O2S3
791.3487, Found: 791.3508.
Results and discussion
Synthesis
2-Cyano-3-(5-(59-(4-(diphenylamino)phenyl)-4,49-dihexyl-
2,29-bithiazol-5-yl)thiophen-2-yl)acrylic acid (BTT-II). The
The synthetic route to the bithiazole-based dyes (BTT-I–III)
containing carbazole, triphenylamine and indoline as elec-
Scheme 1 The synthesis of the dyes BTT-I–III.
15902 | RSC Adv., 2013, 3, 15900–15908
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