Synthesis and Photophysical Properties of Tetra- and Octasubstituted Phosphorous Oxide Triazatetrabenzcorrole Photosensitizers

The synthesis of phosphorous oxide triazatetrabenzcorroles (TBC) tetra- (9, 11) or octa- (13) substituted on the ring with halogenated functional groups is reported. The complexes are not aggregated in dimethylsulfoxide (DMSO) and show solubility in solvents such as pyridine. The Q band absorption spectra of the complexes are red-shifted compared to unsubstituted PTBC. The latter complex shows a large triplet lifetime (1.7 milliseconds), higher than for MPc derivatives. The chlorinated derivatives show good triplet yields (Φ(T)∼ 0.46 and 0.36) and relatively long lifetimes (256 and 452 microseconds), respectively, for 11 and 13.