A liquid-crystalline perylene tetracarboxylic bisimide derivative bearing a triethylene oxide chain and complexation of the derivative with Li cations

Abstract

A liquid-crystalline (LC) perylene tetracarboxylic bisimide (PTCBI) derivative bearing a triethylene oxide chain as well as two pentamethyldisiloxane chains was synthesized. This compound exhibits an ordered lamellar phase at room temperature, and the LC phase is retained when the sample is cooled to −100 °C. Due to the presence of extended π-conjugated perylene rings, efficient electron transport occurs in the lamellar phase and the electron mobility exceeds 1 × 10⁻³ cm² V⁻¹ s⁻¹ at room temperature. Moreover, this PTCBI derivative can form a complex with lithium triflate because of the polar triethylene oxide chain. Lithium triflate can be mixed with it up to 3 mol%. Up to this concentration, the lamellar LC structure and the electron transport properties are not perturbed by the presence of the ionic species.