One-Pot Strategy for Symmetrical and Unsymmetrical BOIMPY Fluorophores.

We report the improved direct access to red-emitting BOIMPY fluorophores (λ ≈ 600 nm) via a simple one-pot approach. Our method starts from easily available benzimidazole-2-carboxylic acids and not only greatly improves the overall yields but also saves both costly reagents and time. In addition, the method facilitates the synthesis of novel unsymmetrical BOIMPY motifs. Therefore, these BOIMPY scaffolds derived from the BODIPY core become more accessible for applications as fluorophores at the appealing red edge of the visible spectrum.