Synthesis and determination of photophysical properties to bodipy benzimidazole compounds

This thesis covers the synthesis of some BODIPY derivatives containing 2-phenyl benzimidazole group in the meso (8) position, elucidation of their structures and determination of their photophysical properties. The study includes stepwise synthesis reactions, and in the first stage, the first serie of the BODIPYs (compounds A1, B1 and C1) were synthesized from an aromatic aldehyde (4-(5,5-dimethyl-1,3-dioxan-2-yl)benzaldehyde) containing protecting group and pyrrole derivatives (2,4-diphenyl-1H pyrrole, 2,4-bis(4- methoxyphenyl)-1H pyrrole and 2,4-diethyl-3-ethyl-1H pyrrole). These compounds were hydrolyzed with trifluoroacetic acid in THF:H2O media to obtain formyl-substituted BODIPY intermediates (A2, B2 and C2, respectively). The aldehyde (formyl) groups were used as building blocks to form the benzimidazole group at the meso (8) position of the BODIPY core. In the last stage, BODIPY compounds containing formyl groups were reacted with ophenylenediamine derivatives in DMF under p-toluenesulfonic acid catalysis to obtain the final benzimidazole-BODIPY derivatives (compounds A3, B3, B4 and C3). Structural characterizations of the synthesized compounds were carried out using 1H, 13C-NMR, HRMS and FTIR techniques. The photophysical parameters were determined by taking the absorption and fluorescence spectra of the compounds in solution, in addition to singlet oxygen quantum yields (ΦΔ) of the final compounds