Liquid Crystallinity and Luminescence Behavior of Cyclic Trinuclear Gold(I) Complexes with Branched Alkyl Side Chains

Abstract

Aggregation-induced emission (AIE) materials have been expected to be applied as luminescent materials. So far, we have synthesized liquid-crystalline trinuclear Au complexes and reported their AIE behavior. Furthermore, we have found that luminescence properties of those complexes depending on the length of the alkyl side-chains. In this study, we introduced the branched side-chains via ester linkage and discussed the relationship between their structure and photophysical/thermal properties. The melting points of complexes were lowered by the introduction of the branched side-chains. In particular, the complex with the longest branch, E-Hex, showed the melting point at -15 °C and discotic nematic phase (ND) in extremely wide temperature range. These Au complexes exhibited strong phosphorescence with AIE properties at room temperature.