ORGANIC
LETTERS
2009
Vol. 11, No. 15
3230-3233
Synthesis, Polymerization, and Unusual
Properties of New Star-Shaped
Thiophene Oligomers
Tyler Taerum, Olena Lukoyanova, Ryan G. Wylie, and Dmitrii F. Perepichka*
Department of Chemistry, McGill UniVersity, Montreal, Quebec H3A 2K6, Canada
Received May 21, 2009
ABSTRACT
Terthienobenzene (TTB, 6) was prepared through a new, high yield route along with π-extended derivatives 10 and 11. Electropolymerization
of tris-EDOT derivative 11 results in a highly stable cross-linked conjugated polymer that shows polaron confinement between the TTB units
as confirmed by UV-vis-NIR spectroelectrochemistry and EPR.
Thiophene-based π-conjugated oligomers with complex
molecular architectures such as star-shaped,1 X-shaped2 and
dendritic3 oligothiophenes have been the focus of recent
research4 as promising organic semiconductors. Their in-
creased dimensionality (2D or 3D), different from the linear
structure of most conjugated oligomers and polymers, offers
new opportunities to control the morphology of the material
in thin film devices5,6 and to build new nanostructured
materials.7
Star-shaped oligothiophenes have been constructed with
benzene,1a triarylamine,8 truxene9 and several other cores,
and in every instance, the steric constraints of the core
resulted in rotation of the linked (oligo)thiophene arms out
of the plane. Roncali’s group has previously reported
synthesis1d and remarkable performance in photovoltaic
devices10 of star-shaped oligothiophenes based on ter-
thienobenzene (TTB, 6) core. The improved semiconducting
(5) Cravino, A.; Roquet, S.; Aleveque, O.; Leriche, P.; Frere, P.; Roncali,
J. Chem. Mater. 2006, 18, 2584.
(1) (a) Che´rioux, F.; Guyard, L. AdV. Funct. Mater. 2001, 11, 305. (b)
Ponomarenko, S.; Kirchmeyer, S.; Elschner, A.; Huisman, B.-H.; Karbach,
A.; Drechsler, D. AdV. Funct. Mater. 2003, 13, 3043. (c) Pappenfus, T. M.;
Mann, K. R. Org. Lett. 2002, 4, 3044. (d) Nicolas, Y.; Blanchard, P.;
Levillain, E.; Allain, M.; Mercier, N.; Roncali, J. Org. Lett. 2004, 6, 273.
(2) Sun, X.; Liu, Y.; Chen, S.; Qiu, W.; Yu, G.; Ma, Y.; Qi, T.; Zhang,
H.; Xu, X.; Zhu, D. AdV. Funct. Mater. 2006, 16, 917.
(6) (a) Cho, M. Y.; Kim, S. J.; Han, Y. D.; Park, D. H.; Kim, K. H.;
Choi, D. H.; Joo, J. AdV. Funct. Mater. 2008, 18, 2905. (b) Sun, Y.; Xiao,
K.; Liu, Y.; Wang, J.; Pei, J.; Yu, G.; Zhu, D. AdV. Funct. Mater. 2005,
15, 818.
(7) Tour, J. M. Chem. ReV. 1996, 96, 537.
(8) Chahma, M.; Gilroy, J. B.; Hicks, R. G. J. Mater. Chem. 2007, 17,
4768.
(3) Xia, C.; Fan, X.; Locklin, J.; Advincula, R. C. Org. Lett. 2002, 4,
2067. (b) Ma, C.-Q.; Mena-Osteritz, E.; Debaerdemaeker, T.; Wienk, M. M.;
Janssen, R. A.; Ba¨uerle, P. Angew. Chem., Int. Ed. 2007, 46, 1679.
(4) Mishra, A.; Ma, C.-O.; Ba¨uerle, P. Chem. ReV. 2009, 109, 1141.
(9) Pei, J.; Wang, J.-L.; Cao, X.-Y.; Zhou, X.-H.; Zhang, H.-B. J. Am.
Chem. Soc. 2003, 125, 9944.
(10) De Bettignies, R.; Nicolas, Y.; Blanchard, P.; Levillain, E.; Nunzi,
J.-M.; Roncali, J. AdV. Mater. 2003, 15, 1939.
10.1021/ol901127q CCC: $40.75
Published on Web 07/02/2009
2009 American Chemical Society