Enhanced Circularly Polarized Luminescence of Urea-Bridged Dimers of Axially Chiral BODIPY-Carbohydrate Hybrids

Herein, we report the synthesis of novel dimeric urea-bridged BODIPY-carbohydrate conjugates, which display circularly polarized luminescence (CPL). The dimers are composed of diastereomerically pure, axially chiral (P or M) BODIPY monomers containing a pendant glucose (d- or l-) unit. The latter was intended to add chirality, biocompatibility, and enhanced water solubility and facilitate the chromatographic resolution of the intermediate atropisomers. The dimerization process was based on the ureation reaction of azidomethyl BODIPYs. The rigorous structural assignment was possible by X-ray diffraction analysis of one of the BODIPY atropisomers.