Issue 30, 2022

Synthesis and optoelectronic properties of air-stable π-conjugated polymers containing both thiophene-2,5-diyl and fused titanacycle units

Abstract

π-Conjugated poly(arylene ethynylene)s containing both thiophene-2,5-diyl and fused metallacycles such as titanafluorene-diyl and dithienotitanacyclopentadiene-diyl units in their alternating sequence were synthesized and their optoelectronic features were studied by the UV-vis spectra and theoretical calculations. The polymerization of 2,5-diethynyl-3-dodecylthiophene and arylene dihalides possessing fused organometallic units such as a 2,7-dibromo-9-titanafluorene and a 5,5′-diiodo-dithienotitanacyclopentadiene was carried out at 70 °C for 48 h in tetrahydrofuran (THF) in the presence of palladium dichloride/4,5-bis(diphenylphosphino)-9,9-dimethylxanthene as a catalyst and diisopropylamine as a base to produce black purple-colored polymers in 51% and 49% yields, respectively. The polymers are soluble in organic solvents such as THF, chloroform, and dichloromethane and they are stable under air at ambient temperature. In the UV-vis absorption spectra of the polymers thus obtained, the absorption maxima (λmax) were observed at 395 nm and 486 nm, respectively, which are bathochromically shifted compared to those of model compounds, 2,7-bis(2-thienylethynyl)titanafluorene and 5,5′-bis(2-thienylethynyl)dithienotitanacyclopentadiene derivatives (λmax = 372 and 418 nm, respectively). The optical band gap (Eoptg) of the polymer containing the titanafluorene unit is estimated to be 2.28 eV on the basis of the absorption onset, which is narrower than that of the model compound, the bis(thienylethynyl)titanafluorene derivative (3.06 eV). In the case of the polymer containing the dithienotitanacyclopentadiene unit, Eoptg was estimated to be 2.12 eV, which is also narrower than that of the model compound, the 5,5′-bis(2-thienylethynyl)dithienotitanacyclopentadiene derivative (2.51 eV).

Graphical abstract: Synthesis and optoelectronic properties of air-stable π-conjugated polymers containing both thiophene-2,5-diyl and fused titanacycle units

Supplementary files

Article information

Article type
Paper
Submitted
20 فروردین 1401
Accepted
04 تیر 1401
First published
06 تیر 1401

Polym. Chem., 2022,13, 4446-4452

Synthesis and optoelectronic properties of air-stable π-conjugated polymers containing both thiophene-2,5-diyl and fused titanacycle units

A. Tanudjaja, M. Higuchi, T. Imai, Y. Matsumura, R. Hifumi, S. Inagi and I. Tomita, Polym. Chem., 2022, 13, 4446 DOI: 10.1039/D2PY00452F

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements