One, Two Three - Phosphaalkene Decoration Tailoring Solubility and Electronic Properties of Truxene-Based Electron Acceptors.

Abstract

We report the functionalization and deplanarization of truxenes using pnictaalkene fragments. Selective introduction of one, two, or three Mes*-Pn fragments provides up to three fully reversible reductions based on the Pn=C fragments. The incorporation of the unsaturated heteroelement fragment as well as the contortion of the truxene core result in significantly red-shifted absorption spectra and interesting opto-electronic properties which are studied by electrochemistry and spectro-electrochemistry. Incorporation of arsaalkene (As=C) motifs gives significantly milder reduction potentials and red-shifted absorption, while phosphaalkene decorated truxene P3 can be functionalized using Au(I)Cl coordination. Furthermore, solubility is markedly increased upon incorporation of the Pn-Mes* fragments which renders these materials suitable for solution processing.