Synthesis and characterization of aryl-substituted BODIPY dyes displaying distinct solvatochromic singlet oxygen photosensitization efficiencies

Singlet Fission from Upper Excited States of Bodipy Crystalline Film and Single Crystal

“…20,47−53 For example, in bodipy-hexaoxatriphenylene conjugates, triplet ESA of the bodipy chromophore is peaked at λ TT = 527 nm, 52 and in naphthylamine-substituted bodipy solution, it is peaked at λ TT = 550 nm. 21 Both results were obtained by using fs TA techniques. With ns flash photolysis, TA of the triplet state was obtained in a tetramethylsubstituted bodipy-anthracene dyad with λ TT = 520−610 nm 51 and in iodo-PhBDP with λ TT = 443 nm and 550−750 nm.…”

“…Triplet transients are not observed in the solution and amorphous film, indicating the formation of the PhBDP triplet state is related to the molecular packing. Furthermore, the lifetime of the triplet state in the crystalline film was obtained by applying nanosecond flash photolysis with 355 nm excitation: τ T = 170 ns (Figure S15), which is significantly shorter than τ T = 50.12 μs of diiodo-PhBDP in toluene, 20 85 μs of PhBDP in the benzimidazole−PhBDP system, 21 and 241.6 μs of the iodo-PhBDP dimer in toluene. 19 The shortening of the triplet lifetime can be explained in terms of the correlated triplet pair that has lost electronic coherent coupling but retains spin coherence.…”

“…Since the B and C (GSB) bands in the crystalline film are long-lived, we consider that they are derived from the triplet states. For different bodipys, triplet states formed via ISC were studied and respective triplet–triplet absorption spectra were reported in a number of publications. ,− For example, in bodipy-hexaoxatriphenylene conjugates, triplet ESA of the bodipy chromophore is peaked at λ TT = 527 nm, and in naphthylamine-substituted bodipy solution, it is peaked at λ TT = 550 nm . Both results were obtained by using fs TA techniques.…”

“…meso -Phenyl-substituted bodipy (PhBDP) is a basic and commercially available compound among abundant bodipy derivatives (Figure ). The heavy atom effect and resonance energy transfer in multichromophores were reported to be responsible for the triplet formation of PhBDP via intersystem crossing (ISC). − However, the triplet state of isolated PhBDP, including in solids (films, crystals), has not been carefully investigated yet. Thus, it is meaningful to further inspect the fundamental photophysical mechanisms of this molecule.…”

Anion Colorimetric Chemosensor Based on a Benzimidazole-Functionalized BODIPY Derivative

“…Among chemosensors based on organic molecules, BODIPY is a multifaceted signaling scaffold that displays notable photophysical properties, such as sharp absorption and emission patterns, a high molar extinction coefficient, high fluorescence quantum yield and good photostability under physiological conditions. The BODIPY core can be modified through chemical functionalization to modulate its photophysical properties and to introduce selective recognition sites for a higher target binding affinity [5][6][7][8][9][10][11][12][13][14][15]. Moreover, (benz)imidazole and its derivatives have been investigated as anion and cation recognition systems that exhibit optical changes upon analyte complexation [16][17][18][19][20][21][22].…”