Linear free-energy relationships in semiquinone species and their Mn(II) and Cu(II) complexes

Autor: Benjamin Shepler, Joseph C. Sloop, Mithra Beikmohamadi Marcus, David A. Shultz
Rok vydání: 2011
Předmět:
Zdroj: Journal of Physical Organic Chemistry. 25:101-109
ISSN: 0894-3230
DOI: 10.1002/poc.1878
Popis: Linear free-energy relationships for a series of functionalized semiquinone ligands and their MnII- and CuIIhydro-tris(3-cumenyl-5-methylpyrazolyl) borate complexes were examined. Quinone–semiquinone cycle half-wave reduction potentials and semiquinone hydrogen hyperfine coupling constants (aH) were determined and their correlation with Hammett σ parameters reported. A new σ parameter, σaH, has been proposed. MnII and CuII metal complex metal–ligand charge transfer and n π* UV transitions were found to be modulated by substituents. Satisfactory Hammett correlations between UV transitions and various σ values have been determined and compared in a number of instances. Copyright © 2011 John Wiley & Sons, Ltd.
Databáze: OpenAIRE