Synthesis, supramolecular structures and luminescent properties of quinacridone derivatives bearing carbazole groups

The syntheses of three carbazyl-containing quinacridone derivatives, N,N′-di((N-carbazyl)-n-butyl) quinacridone (DCBQA), N,N′-di((N-carbazyl)-n-hexyl)quinacridone (DCHQA) and N,N′-di((N-carbazyl)-n-octyl)quinacridone (DCOQA), are reported, and the photoluminescent (PL) characteristics are presented. The single crystal X-ray structures of DCBQA, DCHQA and DCOQA are investigated. The crystal of DCBQA is characterized by intermolecular п•••п interactions between quinacridone cores and carbazole moieties resulting in the formation of DCBQA molecule layer, in which every quinacridone core is surrounded by four carbazole groups. In DCHQA crystal, molecules assemble into two kinds of oriented columns based on intermolecular п•••п interactions between quinacridone cores. The DCOQA crystal displays intermolecular CH•••п and hydrogen bonding interactions feature. In DCOQA solid, every quinacridone core is sandwiched by two alkyl chains from two adjacent DCOQA molecules and simultaneously linked together with two other quinacridone cores by hydrogen bonding interactions. The PL spectra of the three compounds in solution exhibit concentration-dependent properties and their PL quantum causes decrease with the increasing concentration.