Stable Mixed‐Valent Radicals from Platinum(II) Complexes of a Bis(dioxolene) Ligand. Issue 21 (2nd February 2014)

• Record Type: Journal Article
• Authors: Loughrey, Jonathan J.; Sproules, Stephen; McInnes, Eric J. L.; Hardie, Michaele J.; Halcrow, Malcolm A.
• Is Part Of: Chemistry. Volume 20:Issue 21(2014)
• Page Start: 6272
• Page End: 6276
• Publication Date: 2014-02-02
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201304848
• Languages: English
• ISSNs: 0947-6539

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Three diplatinum(II) complexes [{PtL}₂(μ‐thea)] (H₄thea=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<inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pghjsrx2vn" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math altimg="urn:x-wiley:09476539:media:CHEM201304848:tex2gif-sup-1" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mtext> </mml:mtext><mml:mrow><mml:msup><mml:mtext> </mml:mtext><mml:mrow><mml:mtext>.</mml:mtext></mml:mrow></mml:msup></mml:mrow></mml:msup></mml:math></alternatives></inline-formula>]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 thea⁴⁻ ligand may lead to an increased through‐space interaction between the dioxolene π systems.</p> </abstract>