Electronic Tuning of Mixed Quinoidal‐Aromatic Conjugated Polyelectrolytes: Direct Ionic Substitution on Polymer Main‐Chains. Issue 50 (28th October 2019)

• Record Type: Journal Article
• Authors: Anderson, Christopher L.; Dai, Nan; Teat, Simon J.; He, Bo; Wang, Shu; Liu, Yi
• Is Part Of: Angewandte Chemie international edition. Volume 58:Issue 50(2019)
• Page Start: 17978
• Page End: 17985
• Publication Date: 2019-10-28
• Subjects: conjugated polymers -- density-functional calculations -- materials science -- photothermal therapy -- polymers; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201908609
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: The synthesis of conjugated polymers with ionic substituents directly bound to their main chain repeat units is a strategy for generating strongly electron‐accepting conjugated polyelectrolytes, as demonstrated through the synthesis of a series of ionic azaquinodimethane (iAQM) compounds. The introduction of cationic substituents onto the quinoidal para ‐azaquinodimethane (AQM) core gives rise to a strongly electron‐accepting building block, which can be employed in the synthesis of ionic small molecules and conjugated polyelectrolytes (CPEs). Electrochemical measurements alongside theoretical calculations indicate notably low‐lying LUMO values for the iAQMs. The optical band gaps measured for these compounds are highly tunable based on structure, ranging from 2.30 eV in small molecules down to 1.22 eV in polymers. The iAQM small molecules and CPEs showcase the band gap reduction effects of combining the donor‐acceptor strategy with the bond‐length alternation reduction strategy. As a demonstration of their utility, the iAQM CPEs so generated were used as active agents in photothermal therapy. Abstract : All in the mix : Conjugated polyelectrolytes are a class of conjugated polymers with ionic substituents. The direct ionic substitution of mixed quinoidal‐aromatic polymers is shown to be an efficient strategy for forming low band gap conjugated polyelectrolytes. These materials display high activity in photothermal therapy applications.