Oxygen-Bridged Diphenylnaphthylamine as a Scaffold for Full-Color Circularly Polarized Luminescent Materials

An oxygen-bridged diphenylnaphthylamine with a helical shape was designed and synthesized as a key scaffold for circularly polarized luminescent (CPL) materials. The introduction of electron-withdrawing groups, such as formyl and 2,2-dicyanovinyl substituents at the naphthyl moiety in this skeleton effectively decreases the LUMO level and thus allows a tuning of the band gap. The prepared model compounds exhibit intense CPL signals with a dissymmetry factor (g value) of 10^-3 both in CH₂Cl₂ solutions and in the solid states. The emission colors of these derivatives are influenced both by the substituents as well as by solvent effects, covering the whole visible region from blue to deep red.