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Transformation of regioregular organotitanium polymers into group 16 heterole-containing π-conjugated materials
Hiroki Nishiyama1, Tomoko Kino, Ikuyoshi Tomita
1Department of Electronic Chemistry, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259, G1-9, Nagatsuta, Yokohama, 226-8502, Japan.
Abstract:
Regioregular organometallic polymers with titanacyclopentadiene units, obtained from terminal diynes and a low-valent titanium complex, were subjected to reactions with disulfur dichloride and selenium (I) chloride to give π-conjugated polymers with thiophene and selenophene units in the main chain in 63% and 86% yields. Their number-average molecular weights were estimated as 4300 and 5700, respectively. Both polymers were found to be fully π-conjugated and their HOMO energy levels were remarkably high (-5.3 eV and -5.0 eV for thiophene- and selenophene-containing polymers, respectively) as supported by their UV-vis absorption spectra and CV analyses.
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