Vanadyl(IV) porphyrin dimers with palladium(II) and platinum(II) linkages: syntheses, electronic properties and magnetic interactions between the two moieties
Résumé
We report the synthesis of new vanadylporphyrins bearing peripheral coordination sites. By using palladium(II) or platinum(II) as connecting ions, porphyrin dimers were isolated and characterized by X-ray crystallography. These paramagnetic species were studied by electronic spectroscopy and Continuous Wave Electron Paramagnetic Resonance (CW EPR). Large bathochromic shifts were observed by comparing porphyrin monomers and dimers showing that electronic delocalization was present as demonstrated earlier for diamagnetic compounds. Despite the large distance (> 14 Å) between the two vanadyl centers in these dimers, small dipolar interactions between the two paramagnetic ions could be determined.
Domaines
Chimie
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