A Novel Heavy-Atom-Free Approach to the Synthesis of Asymmetric α,α-Ethene-Bridged BODIPY Dimers

Abstract BODIPY bichromophores are of great interest due to their unique photophysical properties, which significantly distinguish them from BODIPY monomers and open up excellent prospects for their various applications. Thus, ethene/ethylene-bridged BODIPY dimers are usually may be concerned as intramolecular J-aggregates with significant exciton coupling and absorption in the NIR region. However, the synthesis of asymmetric α,α-ethene-bridged BODIPY dimers is limited by Stille cross-coupling reactions, without the possibility of obtaining α,α-ethene-bridged BODIPY dimers. Herein, we propose a novel approach to the synthesis of an asymmetric ethene-bridged α-α BODIPY dimer without cross-coupling reaction, which opens up the possibility of synthesis without the use of expensive cross-coupling reagents from readily available reagents.