Synthesis and properties of dimethoxytriphenylamine- based enamines

Abstract

This article describes the synthesis and properties of new methoxy-substituted triphenylamine-based enamines. Thermal, photophysical and electrochemical properties of the compounds are reported. In addition, the ionisation energies estimated by photoelectron emission spectroscopy and hole transporting properties examined by the time-of-flight method are discussed. The compounds form molecular glasses with glass transition temperatures of up to 91°C. They exhibit a high thermal stability with 5% weight-loss temperatures above 420°C. Their characteristic optical band-gaps are of 2.9 eV and the solid-state ionisation energies situate around 5.4 eV. One of the compounds shows a high hole mobility of 8.4 × 10–4 cm2/Vs at the electric field of 4 × 105 V/cm.