84849-06-9Relevant academic research and scientific papers
Effect of axial base on dioxygen and carbon monoxide affinities of iron(II) porphyrins. Imidazole vs. pyridine
Collman, James P.,Brauman, John I.,Doxsee, Kenneth M.,Sessler, Jonathan L.,Morris, Roger M.,Gibson, Quentin H.
, p. 1427 - 1432 (2008/10/08)
The synthesis of picket fence porphyrin derivatives bearing covalently attached imidazole and pyridine nuclei is described. The oxygen and carbon monoxide affinities of the iron(II) complexes of these porphyrins are reported. Electronic effects due to replacement of imidazole by pyridine have been isolated from steric constraints. These electronic effects, deriving from a decreased basicity of the axial base, give rise to 40-fold and 13-fold reduction, respectively, in oxygen and carbon monoxide affinities upon replacing imidazole by pyridine. Kinetic measurements of oxygen and carbon monoxide association rates suggest that these changes are manifested primarily in ligand dissociation rates.
