Synthesis and characteristics of novel fluorescence dyes based on chromeno[4,3,2-de][1,6]naphthyridine framework

A series of entirely new framework chromeno[4,3,2-de][1,6]naphthyridine derivatives containing carbazole groups have been carefully designed and prepared. The relationship of photoluminescence property and structure of these compounds was systematically investigated via UV–vis, fluorescence and electrochemical analyzer. The HOMO and LUMO distributions of these compounds were calculated by density functional theory (DFT) (B3LYP; 6-31G∗) method. These compounds exhibited high fluorescence quantum yields, desirable HOMO levels and high thermal stability, indicating that the combination of chromeno[4,3,2-de][1,6]naphthyridine and carbazole could be an efficient means to enhance hole-transporting ability and fluorescent quantum yield.

Graphical abstractEntirely new framework chromeno[4,3,2-de][1,6]naphthyridine derivatives containing carbazole groups were synthesized and the optical, electrochemical properties were also investigated. Quantum chemical calculations were used to obtain optimized ground-state geometry, spatial distributions of the HOMO, LUMO levels of the compounds.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Entirely new framework fluorescence dyes based on naphthyridine were synthesized. ► Compounds exhibited efficient green emission with high quantum yields. ► HOMO energy level were improved by the introduction of the carbazole units. ► Compounds might application in OLEDs as hole-transporting materials.