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DOI: 10.1039/A802315H (Paper) Reference Section for: Chem. Commun., 1998, 1105-1107

Halogen to metal π-donation in metalloporphyrins

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Zeev Gross and Claudia M. Barzilay

Abstract

The 1H NMR analysis of the paramagnetic trans-dihalogeno-ruthenium(IV) and osmium(IV) porphyrins reveals that the halides have a pronounced effect on both the magnitude and the direction of charge transfer between the metal and the porphyrin, that the degree of covalency of metal–halide bonds increases in the order of MnIII < RuIV < OsIV, and that the relative strength of halogen-to-metal π-donation is Cl < Br < I.

References

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  17. Also, the pyrrole-H isotropic shift of the (perchlorato)manganese(III) porphyrin is much lartger than in the halogeno-coordinated derivatives.4.
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