93058-51-6Relevant academic research and scientific papers
Singlet Oxygen Generation in Peripherally Modified Platinum and Palladium Porphyrins: Effect of Triplet Excited State Lifetimes and meso-Substituents on 1O2 Quantum Yields
D'Souza, Francis,D'Souza, Patrick F.,Nesterov, Vladimir N.,Reid, Ryan,Subedi, Dili R.
, (2022/03/18)
A series of meso-substituted with aromatic (=tolyl, pyrenyl, fluorenyl, naphthyl, and triphenylamine) substituents, platinum (Pt), and palladium (Pd) porphyrins have been synthesized and characterized by spectroscopic and single-crystal X-ray diffraction studies to probe structure-reactivity aspects on the electrochemical redox potentials, and phosphorescence quantum yields and lifetimes. In the X-ray structures, the aromatic meso-substituents were rotated to some extent from the planarity of the porphyrin ring to minimize steric hindrance. Both Pt and Pd porphyrins revealed higher electrochemical redox gaps as compared to their free-base porphyrin analogs as a result of the harder oxidation and reduction processes. The ability of both Pt and Pd porphyrins to generate singlet oxygen was probed by monitoring the photoluminescence of 1O2 at 1270 nm. Higher quantum yields for both triplet sensitizers compared to their free-base analogs were witnessed. Singlet oxygen quantum yields close to unity were possible to achieve in the case of Pt and Pd porphyrins bearing triphenylamine substituents at the meso-position. The present study brings out the importance of different meso-substituents on the triplet porphyrin sensitizers in governing singlet oxygen quantum yields; a key property of photosensitizers needed for photodynamic therapy, chemical synthesis, and other pertinent applications.
CHEMICAL DEGRADATION OF GAS-SENSING MESO-TETRA-ARYLPORPHIN THIN FILMS BY HIGH LEVELS OF DINITROGEN TETROXIDE.
Honeybourne, Colin L.,Hill, Callum A. S.
, p. 315 - 322 (2008/10/08)
Thin solid films of free base meso-tetra-arylporphins and their zinc, copper, platinum and palladium complexes have been exposed to high levels of dinitrogen tetroxide (NOX). The optical spectra (300-850 nm) were recorded in transmission before and after
