1620848-93-2Relevant academic research and scientific papers
Stable mixed-valent radicals from platinum(II) complexes of a bis(dioxolene) ligand
Loughrey, Jonathan J.,Sproules, Stephen,McInnes, Eric J. L.,Hardie, Michaele J.,Halcrow, Malcolm A.
, p. 6272 - 6276 (2014)
Three diplatinum(II) complexes [{PtL}2(μ-thea)] (H 4thea=2,3,6,7-tetrahydroxy-9,10-dimethyl-9,10-dihydro-9, 10-ethanoanthracene) have been prepared, with diphosphine or bipyridyl L co-ligands. One-electron oxidation of these complexes gave radical cations containing a mixed-valent [thea .]3- ligand with discrete catecholate and semiquinonate centers separated by quaternary methylene spacers. The electronic character of these radicals is near the Robin-Day class II/III border determined by UV/Vis/NIR and EPR spectroscopies. Crystal-structure determinations and a DFT calculation imply that oxidation of the thea 4- ligand may lead to an increased through-space interaction between the dioxolene π systems. Electron hopping: Diplatinum complexes, such as the one shown here, are readily oxidized to mixed-valent catechol/semiquinone radical species, some of which can be crystallized at room temperature. The dioxolene rings in the radical products are moderately strongly coupled by EPR and UV/Vis/NIR spectroscopies, despite being separated by saturated methylene spacers.
