Extra Coordination of Zn-Tetraphenylporphine with Pyridine, Quinoline, and Acridine N-Oxides

Abstract

The log K values of zinc tetraphenylporphine (Zn-TPhP) complexes with pyridine, quinoline, and acridine N-oxides and with their nonoxidized analogs, as well as the positions of absorption maxima of the complexes with respect to Zn-TPhP linearly depend on the \(pK_{BH^ + }\) of the ligands in water (methanol, acetonitrile, nitromethane, and acetone) and on Hammett σ constants in the absence of steric effects.