Impact of Double-π-Bridge on Bis(triarylamine)-Based Organic Mixed-Valence System: A Case Study of Diaza[1.1](4,4")ortho-terphenylophane Radical Cation

Chemistry. 2024 Dec 23:e202403945. doi: 10.1002/chem.202403945. Online ahead of print.

Abstract

A bis(triarylamine) (BTA) radical cation, bridged by two o-terphenylene moieties, was prepared and characterized to explore the impact of the double-π-bridge on the intramolecular charge/spin transfer process in the 2-site organic mixed-valence (MV) compound. Spectroscopic analyses on optically and thermally assisted intervalence charge-transfer (IVCT) processes revealed that the doubly π-bridging enhanced the charge delocalization between two nitrogen redox-active centers, whereas the electronic coupling was not so strengthened, in comparison with the singly π-bridging reference compound.

Keywords: redox chemistry・radical ions・mixed-valence compounds・arylamine・charge delocalization.