The axial ligand effect of oxo-iron porphyrin catalysts. How does chloride compare to thiolate?

作者: Sam P. de Visser

DOI: 10.1007/S00775-005-0061-X

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摘要: We have performed density functional theory calculations on an oxo-iron porphyrin catalyst with chloride as axial ligand and tested its reactivity toward propene. The reactions proceed via multistate competing doublet quartet spin surfaces. Close-lying epoxidation hydroxylation mechanisms are identified, whereby in the gas phase reaction is dominant, while environments a large dielectric constant pathways become competitive. By contrast to thiolate all low-lying small ring-closure rebound barriers, so it expected that side products rearrangements will be unlikely Fe=O(porphyrin)Cl, whereas Fe=O(porphyrin)SH some were predicted. major differences electronic configurations of Fe=O(porphyrin)Cl due strong mixing orbitals iron 3d orbitals, which much less ligand. Predictions ethylbenzene-h12 versus ethylbenzene-d12 made.

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