HOMO Energy-Level Lifting in p-Type O-Doped Graphenoids: Synthesis of Electrochromic Alkoxy-Decorated Xanthenoxanthenes

Abstract

A series of novel O-doped polycyclic aromatic hydrocarbons, bearing a different number of electron-donating alkoxy substituents, has been prepared using a novel copper-promoted anaerobic protocol for the cyclisation of highly electron rich peri-xanthenoxanthene molecular modules. The effect of the number and position of the alkoxy substituents on the optoelectronic properties has thus been investigated, unveiling p-type semiconducting properties. All molecules displayed a significant colour change upon oxidation, suggesting that these compounds can be used to devise chromogenic materials to engineer electrochromic devices.