Synthesis, Structures, and Properties of Neutral and Radical Cationic S,C,C-Bridged Triphenylamines

Org Lett. 2020 Jan 17;22(2):734-738. doi: 10.1021/acs.orglett.9b04575. Epub 2019 Dec 30.

Abstract

A structurally constrained S,C,C-bridged triphenylamine was synthesized, and the corresponding radical cation was obtained as a hexachloroantimonate by chemical oxidation. An X-ray crystallographic analysis revealed an almost planar structure for this radical cation, which thus represents the first example of a planar, para-unsubstituted triphenylamine radical cation analogue with a sulfur bridge. The electronic properties of the radical cation were examined by UV-vis-NIR and ESR spectroscopy as well as DFT calculations.