Thermodynamics of formation of molecular complexes of metalloporphyrins with pyridine in organic solvents at 298.15 K

Microcalorimetric titration was used to obtain a full set of thermodynamic characteristics of the axial coordination of pyridine by metal complexes of synthetic (ZnTPP, NiTPP, CuTPP, (CI)FeTPP, (Ac)FeTPP, (CI)MnTPP, (Ac)MnTPP ) and biological (ZnHP, ZnDP, ZnMP, ZnPP) porphyrins in benzene and chlorof orm at 298.15 K. It was established that the involved character of the proc esses under study is determined both by the structure of the metalloporphyr ins and by the specific features of the solvation interactions of metallopo rphyrin and pyridine with solvent molecules.