Color-tunable emissive heptagon-embedded polycyclic aromatic dicarboximides

Abstract

Heptagon-embedded polycyclic aromatic dicarboximides were developed as new push–pull fluorescent dyes through palladium-catalysed [4+3] annulation followed by nucleophilic substitution. The introduction of a seven-membered ring in these push–pull systems can efficiently modulate the optical properties leading to an enhancement of the fluorescence quantum yields up to 0.93 with color tunable emission covering the visible-NIR spectrum.