Electrochromic Application of an Enediyne Scaffolding as a Redox-Active Chromophore - Synthesis and Redox Behavior of 9,10-Bis[3-(6-azulenyl)-1-(6-azulenylethynyl)-2-propynylidene]-9,10-dihydroanthracenes

摘要

A bis(enediyne) system utilizing anthraquinodimethane as a platform for a redox-active substructure that bears azulenes as π-electron-accepting groups at the periphery has been prepared by a simple one-pot reaction involving repeated Pd-catalyzed alkynylation of 6-bromoazulenes with the bis(enediyne). The novel bis(enediyne)s exhibited two, one-step two-electron redox properties under electrochemical reduction conditions together with a significant color change owing to the generation of a closed-shell cyanine-type substructure by the two-electron reduction.