Boronic esters: a simple route to discotic liquid crystals that are electron deficient

Abstract

The formation of boronic esters lowers the LUMO energy of hexamethoxytriphenylene by ∼1 V, converting the discotic core archetype from electron-rich to electron-deficient. Cyclic voltammetry gives E_1/2 reduction values (ca. −1.2 V vs. Fc/Fc⁺) that are comparable to that of C₆₀, the standard electron acceptor in organic electronics. Suitable peripheral functionalization imparts large mesophase temperature ranges. Homeotropic, columnar hexagonal phases with good charge carrier mobilities (up to 8 × 10⁻² cm² V⁻¹ s⁻¹) are observed.