Higher BODIPY Homologues-Synthesis, Reactivity, and Photoluminescence Investigations.

The synthesis of DPM group 13 (B─In, DPM = 1,5,9-trimesityldipyrromethene) compounds with halide substituents (Cl─I) is described. All compounds were fully characterized including NMR and IR spectroscopy as well as mass spectrometry. In addition, the solid state molecular structures have been determined by X-ray diffraction (XRD) analysis. As higher representatives of BODIPY (boron difluoride dipyrromethene) dyes, some of these DPM triel dihalides also exhibit an intense green fluorescence when exposed to sunlight. In this regard, the optical properties were investigated by UV/Vis and photoluminescence spectroscopy giving absorption maxima around 520 nm and fluorescence emission in the range between 550 and 660 nm. Fluorescence quantum efficiencies up to 42% could be obtained from measurements in toluene solution. Further, reactivity studies were carried out which opened-up access to mixed substituted DPM triels with one alkyl and one halide substituent.