Effect of meso-phenyl substitution on spectral properties, photo- and thermal stability of boron(III) and zinc(II) dipyrrometenates

Abstract The results of investigation of the spectral characteristics, photostability and thermal degradation of B(III) and Zn(II) complexes with 3,3’,5,5’-tetramethyl-2,2′-dipyrromethene and meso-phenyl-3,3 ',5,5'-tetramethyl-2,2'-dipyrromethene were presented. It has been shown that meso-phenyl substitution in the 3,3', 5,5'-tetramethyl-2,2'-dipyrromethene complexes with B(III) and Zn(II) leads to a hypsochromic displacement S0 → S1 bands in the EAS and a significant increase in its intensity, but a decrease in the fluorescence quantum yield. It has been established that the introduction of phenyl substituent in the meso-position causes an increase in thermal stability (up to 20°C in Bodipy and up to 74°C in Zn-complexes) and photostability (up to 3 times for Bodipy and up to 7 times for Zn(II) dipyrromethenates).