Molecular engineering of thiophene- and pyrrole-fused core arylamine systems: Tuning redox properties, NIR spectral responsiveness and bacterial imaging applications

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Vol. 321; p. 124704
• Main Authors: Peng, Zhen, Lin, Yiling, Deng, Shuangling, Liu, Zhenji, Xia, Yonglin, Ou, Ya-Ping, Zhang, Jing, Hua Liu, Sheng
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 15.11.2024
• Subjects: Amines - chemistry; Arylamine, Reversible multistep redox; Bacteria; Electroluminescence; Near-infrared (NIR) absorption; Oxidation-Reduction; Pyrroles - chemistry; Spectroscopy, Near-Infrared - methods; Thiophenes - chemistry; Visual bacteria identification; Arylamine, Reversible multistep redox; Electroluminescence; Visual bacteria identification; Near-infrared (NIR) absorption
• ISSN: 1386-1425; 1873-3557
• DOI: 10.1016/j.saa.2024.124704

A series of novel dithieno[3,2-b:2′,3′-d]pyrrole (DTP) and tetrathieno[3,2-b:2′,3′-d]pyrrole (TTP) bridged arylamine compounds with varying carbon chain lengths.. These compounds exhibit reversible multistep redox processes, multistep near-infrared absorption alterations, electroluminescent behaviors and rapid visual bacterial identification abilities. [Display omitted] •A series of novel dithieno[3,2-b:2′,3′-d]pyrrole (DTP) and tetrathieno[3,2-b:2′,3′-d]pyrrole (TTP) bridged arylamine compounds has been synthesized.•These compounds exhibited reversible multistep redox processes.•These compounds cation states displayed impressive multistep NIR absorption alterations and unique electroluminescent behaviors.•4,4′-(4-butyl-4H-dithieno[3,2-b:2′,3′-d]pyrrole-2,6-diyl)bis(N,N-diphenylaniline) has the potential for rapid visual identification of bacteria in clinic. The thiophene- and pyrrole-fused heterocyclic compounds have garnered significant interest for their distinctive electron-rich characteristics and notable optoelectronic properties. However, the construction of high-performance systems within this class is of great challenge. Herein, we develop a series of novel dithieno[3,2-b:2′,3′-d] pyrrole (DTP) and tetrathieno[3,2-b:2′,3′-d] pyrrole (TTP) bridged arylamine compounds (DTP-C4, DTP-C12, DTP-C4-Fc, TTP-C4-OMe, TTP-C4, and TTP-C12) with varying carbon chain lengths. The pertinent experimental results reveal that this series of compounds undergo completely reversible multistep redox processes. Notably, TTP-bridged compounds TTP-C4 and TTP-C12 exhibit impressive multistep near-infrared (NIR) absorption alterations with notable color changes and electroluminescent behaviors, which are mainly attributed to the charge transfer transitions from terminal arylamine units to central bridges, as supported by theoretical calculations. Additionally, compound DTP-C4 demonstrates the ability to visually identify gram-positive and gram-negative bacteria. Therefore, this work suggests the promising electroresponsive nature of compounds TTP-C4 and TTP-C12, positioning them as excellent materials for various applications. It also provides a facile approach to constructing high-performance multifunctional luminescent materials, particularly those with strong and long-wavelength NIR absorption capabilities.