Towards the Preparation of Electrochromic Materials with Strong Absorption in the Near-Infrared Region: Synthesis and Redox Behavior of Azulene-Substituted Enediyne Scaffolds Connected by a 9,10-Anthracenediyl Spacer
Enediynescaffoldsconnected by a 9,10-anthracenediylspacer as a redox-active substructure with 6-azulenyl groups as π-electron-accepting groups in their periphery (3a and 3b) have been prepared by a one-pot reaction involving repeated Pd-catalyzed alkynylation of 6-haloazulenes 7b and 7c with bis(enediyne) derivative 6. The azulene-substituted bis(enediyne)s 3a and 3b exhibited two reversible one-step