Ethynylene-Linked Oligomers Based on Benzodithiophene: Synthesis and Photoelectric Properties
References
more octyl groups in carbazole unit. The data verified
the results from theoretical calculations as illustrated in
Table 4 and Figure 8.
[1] Wang, C.; Dong, H.; Hu, W.; Liu, Y.; Zhu, D. Chem. Rev. 2012, 112,
2208.
[2] Zhang, F.; Wu, D.; Xu, Y.; Feng, X. J. Mater. Chem. 2011, 21,
17590.
Table 5 The conductivity of initial oligomer and those doped
[3] Huo, L.; Hou, J. Polym. Chem. 2011, 2, 2453.
[4] Katz, H. E.; Bao, Z.; Gilat, S. L. Acc. Chem. Res. 2001, 34, 359.
[5] Takimiya, K.; Kunugi, Y.; Otsubo, T. Chem. Lett. 2007, 36, 578.
[6] Kashiki, T.; Miyazaki, E.; Takimiya, K. Chem. Lett. 2008, 37, 284.
[7] Pan, H.; Li, Y.; Wu, Y.; Liu, P.; Ong, B. S.; Zhu, S.; Xu, G. Chem.
Mater. 2006, 18, 3237.
[8] Pan, H.; Wu, Y.; Li, Y.; Liu, P.; Ong, B. S.; Zhu, S.; Xu, G. Adv.
Funct. Mater. 2007, 17, 3574.
[9] Pan, H.; Li, Y.; Wu, Y.; Liu, P.; Ong, B. S.; Zhu, S.; Xu, G. J. Am.
Chem. Soc. 2007, 129, 4112.
with iodine
Ratio of Conductivity
iodinea
Ratio of Conductivity
Oligomer
Oligomer
σ/(S•cm−1)
1.05×10−15
4.37×10−12
1.23×10−10
σ/(S• cm−1)
6.98×10−16
1.33×10−12
1.05×10−10
iodine
0%
0%
O1
O1
O1
O2
O2
O2
10%
30%
10%
30%
a Ratio of iodine-the quality percentage of iodine in oligomers.
[10] Chen, L.; Shen, X.; Chen, Y. Chin. J. Chem. 2012, 30, 2219.
[11] Laquindanum, J. G.; Katz, H. E.; Lovinger, A. J.; Dodabalapur, A.
Adv. Mater. 1997, 9, 36.
[12] Leenen, M. A. M.; Cucinotta, F.; Viani, L.; Mavrinskiy, A.; Pisula,
W.; Gierschner, J.; Cornil, J.; Schwab, A. P.; Thiem, H.; Müllen, K.;
Cola, L. C. J. Phys. Chem. B 2010, 114, 14614.
[13] Meng, Q.; Jiang, L.; Wei, Z.; Wang, C.; Zhao, H.; Li, H.; Xu, W.; Hu,
W. J. Mater. Chem. 2012, 20, 10931.
[14] Sista, P.; Bhatt, M. P.; Mccary, A. R.; Nguyen, H.; Hao, J.; Biewer,
M. C.; Stefan, M. C. J. Polym. Sci., Part A: Polym. Chem. 2011, 49,
2292.
When polymer was exposed to iodine, the polymer
was oxidized by iodine and electron was moved out
from polymer. Then the polymer was translated into
cation radical, which was so instable that it would cap-
ture another electron from adjacent unsaturated bond,
generating new cation radical. As the process repeated,
the electron could transfer along the conjugated chain.[46]
For O1 and O2, an electron was captured from large
conjugated system by iodine, then the electron hole was
stuffed by adjacent electron, thereby the electron flowed
along conjugated chain (BDT unit and benzothiadiazole
or carbazole). When the iodine was doped into O1 and
O2, the conductivity of oligomers acquired enormous
changes. The electrical behavior of oligomers showed
translation from insulator to semi-conductor after the
addition of iodine. The conductivity increased obviously
with the addition of iodine.
[15] Hou, J.; Park, M. H.; Zhang, S.; Yao, Y.; Chen, L. M.; Li, J. H.; Yang,
Y. Macromolecules 2008, 41, 6012.
[16] Braunecker, W. A.; Oosterhout, S. D.; Owczarczyk, Z. R.; Larsen, R.
E.; Larson, B. W.; Ginley, D. S.; Boltalina, O. V.; Strauss, S. H.;
Kopidakis, N.; Olson, D. C. Macromolecules 2013, 46, 3367.
[17] Huo, L.; Zhang, S.; Guo, X.; Xu, F.; Li, Y.; Hou, J. Angew. Chem.,
Int. Ed. 2011, 50, 9697.
[18] Shen, P.; Bin, H.; Chen, X.; Li, Y. Org. Electron. 2013, 14, 3152.
[19] Hou, J.; Chen, H. Y.; Zhang, S.; Chen, R. I.; Yang, Y.; Wu, Y.; Li, G.
J. Am. Chem. Soc. 2009, 131, 15586.
[20] Piliego, C.; Holcombe, T. W.; Douglas, J. D.; Woo, C. H.; BeauJuge,
P. M.; Fréchet, J. M. J. J. Am. Chem. Soc. 2010, 132, 7595.
[21] Price, S. C.; Stuart, A. C.; Yang, L.; Zhou, H.; You, W. J. Am. Chem.
Soc. 2011, 133, 4625.
[22] Hu, C.; Zhang, Q. Chin. J. Chem. 2013, 31, 1404.
[23] Zhan, X.; Zhu, D. Polym. Chem. 2010, 1, 409.
[24] Boudreault, P. L. T.; NaJari, A.; Leclerc, M. Chem. Mater. 2011, 23,
456.
[25] Wang, B.; Tsang, S. W.; Zhang, W.; Tao, Y.; Wong, M. S. Chem.
Commun. 2011, 47, 9471.
[26] Misra, R.; Gautam, P.; Sharma, R.; Mobin, S. M. Tetrahedron Lett.
2013, 54, 381.
[27] Zeng, S.; Yin, L.; Jiang, X.; Li, Y.; Li, K. Dyes Pigm. 2012, 95, 229.
[28] Wang, J. T.; Ye, H. Y.; Li, H. J.; Mei, C. Y.; Ling, J.; Li, W. S.; Shen,
Z. Q. Chin. J. Chem. 2013, 31, 1367.
[29] Chen, S. C.; Tang, C. Q.; Yin, Z. G.; Ma, Y. L.; Cai, D. D.; Ganeshan,
D.; Zheng, Q. D. Chin. J. Chem. 2013, 31, 1409.
[30] Hu, B.; Wang, Y.; Chen, X.; Zhao, Z.; Jiang, Z.; Lu, P.; Wang, Y.
Tetrahedron 2010, 66, 7583.
[31] Miao, H. M.; Zhang, H. L.; Xu, J. K.; Fan, C. L.; Dong, L.; Zeng, L.
Q.; Zhao, F. Chin. J. Chem. 2008, 26, 1922.
Conclusions
Two novel organic conjugated oligomers, O1 and
O2, were successfully synthesized by Pd(II)-catalyzed
Sonogashira coupling reaction. O2 was very soluble in
normal organic solvents due to containing octyl group.
The degree of polymerization of O1 is 7, and that of O2
is 10. Both of them have a good PDI. O2 was more
thermally stable than O1. UV-Vis, CV and theoretical
calculations show that O1 had a lower band gap than
O2, and O1 had a strong absorption peak which was 54
nm red shifted to O2. This phenomenon may be as-
cribed to the difference of their molecular structures.
The stocks shift is about 145 nm for both O1 and O2.
From the results of electrical conductivity, O1 and O2
showed semi-conductor behavior when doped with io-
dine, which makes these oligomers have potential ap-
plications in organic photoelectric materials.
[32] Zhang, X. C.; Wang, C. Y.; Lai, G. Q.; Zhang, L.; Shen, Y. J. Polym.
Bull. 2011, 66, 893.
Acknowledgement
[33] Miyaura, N.; Suzuki, A. Org. Synth. 1993, 8, 532.
[34] Lee, P.; Hsu, S. L.; Lee, J. F.; Chuang, H. Y.; Lin, P. J. Polym. Sci.,
Part A: Polym. Chem. 2011, 49, 662.
[35] Li, Y.; Xu, B.; Li, H.; Cheng, W.; Xue, L.; Chen, F.; Lu, H.; Tian, W.
J. Phys. Chem. C 2011, 115, 2386.
The authors are grateful to financial support from the
National Natural Science Foundation of China (Nos.
20872035, 21076078), and the East China University of
Science and Technology.
[36] Zhang, T. T.; Zhu, C. Q.; Ma, Y. W.; Wang, C. Y.; Shen, Y. J. Chin. J.
Chin. J. Chem. 2014, 32, 298—306
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