Bis-N-annulated quaterrylenebis(dicarboximide) as a new soluble and stable near-infrared dye.

A new ladder-type bis-N-annulated quaterrylenebis(dicarboximide) (1) was synthesized, and it exhibits excellent solubility in common organic solvents, high molar absorptivity, and good stability. Moreover, it absorbs and emits light in the near-IR spectral region with a high fluorescence quantum yield. All these properties qualify it as a promising NIR dye for many applications.