Cyanine–cyanine hybrid structure as a stabilized polyelectrochromic system: synthesis, stabilities, and redox behavior of di(1-azulenyl)methylium units connected with electron-accepting π-electron systems

Abstract

This paper describes preparation of the two-types of cations composed of di(1-azulenyl)methylium units based on a new structural principle of cyanine-cyanine (C-C) hybrid for the design of polyelectrochromic materials. Voltammetric analysis of these cations revealed the idealized reversible two-step, two-electron redox properties. Two-step color changes presumed by their C-C hybrid structure were revealed by their electrochemical reduction. The scope of the creation of the stabilized polyelectrochromic materials taking the new structural principle with azulene skeletons is demonstrated by two-types of examples.

Persistent azulene α-carbocations: synthesis from aldehydes, spectroscopic and crystallographic properties

“…There are few reports of α-aryl cations in conjugation with nitro groups, but such salts can be isolable when other electron-donating groups are also present. 33 We next sought to characterise the novel salts crystallographically and were able to obtain X-ray structures for 25 (Fig. 3), 26 (Fig.…”