Abstract
Equilibrium constants for the binding of sulfur bases to cobalt(II) porphyrins were measured in toluene solution by a spectrophotometric method. The order of decreasing binding strength of sulfur ligands to cobalt(II) porphyrins was found to be mercaptide ions » thioethers > mercaptans. It is suggested that a similar stability order of these sulfur ligands should exist towards iron(II) porphyrins, but formation constants could be obtained only for the mercaptide ions.
Keywords: equilibrium constants, cytochrome P-450 mechanism
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