Khalil Youssef, Antoine Vacher, Thanaphon Khrueawatthanawet, Thierry Roisnel, Frédéric Barrière and Dominique Lorcy
{"title":"Electrostatic vs. electronic interactions within oxidized multinuclear Pt(bipyridine)(dithiolene) complexes†","authors":"Khalil Youssef, Antoine Vacher, Thanaphon Khrueawatthanawet, Thierry Roisnel, Frédéric Barrière and Dominique Lorcy","doi":"10.1039/D4DT02514H","DOIUrl":null,"url":null,"abstract":"<p >Bi- and trimetallic platinum(bipyridine)(dithiolene) complexes involving different organic linkers between the redox active platinum(dithiolene) moieties have been synthesized and studied by electrochemistry and spectroelectrochemistry. Cyclic voltammetry experiments carried out on these multinuclear complexes in dichloromethane using [NBu<small><sub>4</sub></small>][PF<small><sub>6</sub></small>] as the supporting salt show only one oxidation process involving the metallacycles. Nevertheless, spectro-electrochemical studies, carried out under the same conditions, show a different evolution of the spectra during oxidation depending on the position of the metallacycles on the phenyl ring. For instance, only the 1,3-disubtituted (<strong>Pt<small><sub>2</sub></small>1,3-P</strong>) and 1,3,5-trisubstituted (<strong>Pt<small><sub>3</sub></small>1,3,5-P</strong>) complexes show the growth of an absorption band in the NIR region upon oxidation while it was not observed for the other complexes. In contrast, electrochemical studies carried out using the poorly coordinating supporting electrolyte, [Na][B(C<small><sub>6</sub></small>H<small><sub>4</sub></small>(CF<small><sub>3</sub></small>)<small><sub>2</sub></small>)<small><sub>4</sub></small>], indicate sequential oxidation of the redox centers with Δ<em>E</em> values varying according to the nature of the bridge and the distance between metal centers. For all the investigated multinuclear complexes, spectro-electrochemical experiments performed in the presence of [Na][B(C<small><sub>6</sub></small>H<small><sub>4</sub></small>(CF<small><sub>3</sub></small>)<small><sub>2</sub></small>)<small><sub>4</sub></small>] show an absorption band in the NIR region consistent with appreciable electrostatic effects and charge delocalization in the mixed valent intermediates.</p>","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":" 48","pages":" 19388-19402"},"PeriodicalIF":3.5000,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Dalton Transactions","FirstCategoryId":"92","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2024/dt/d4dt02514h","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, INORGANIC & NUCLEAR","Score":null,"Total":0}
引用次数: 0
Abstract
Bi- and trimetallic platinum(bipyridine)(dithiolene) complexes involving different organic linkers between the redox active platinum(dithiolene) moieties have been synthesized and studied by electrochemistry and spectroelectrochemistry. Cyclic voltammetry experiments carried out on these multinuclear complexes in dichloromethane using [NBu4][PF6] as the supporting salt show only one oxidation process involving the metallacycles. Nevertheless, spectro-electrochemical studies, carried out under the same conditions, show a different evolution of the spectra during oxidation depending on the position of the metallacycles on the phenyl ring. For instance, only the 1,3-disubtituted (Pt21,3-P) and 1,3,5-trisubstituted (Pt31,3,5-P) complexes show the growth of an absorption band in the NIR region upon oxidation while it was not observed for the other complexes. In contrast, electrochemical studies carried out using the poorly coordinating supporting electrolyte, [Na][B(C6H4(CF3)2)4], indicate sequential oxidation of the redox centers with ΔE values varying according to the nature of the bridge and the distance between metal centers. For all the investigated multinuclear complexes, spectro-electrochemical experiments performed in the presence of [Na][B(C6H4(CF3)2)4] show an absorption band in the NIR region consistent with appreciable electrostatic effects and charge delocalization in the mixed valent intermediates.
期刊介绍:
Dalton Transactions is a journal for all areas of inorganic chemistry, which encompasses the organometallic, bioinorganic and materials chemistry of the elements, with applications including synthesis, catalysis, energy conversion/storage, electrical devices and medicine. Dalton Transactions welcomes high-quality, original submissions in all of these areas and more, where the advancement of knowledge in inorganic chemistry is significant.