The bi-sandwich complex [Fe2Fv(C6H6)2]2+(PF6-)2 (12+; Fv = μ2-η5:η5-fulvalenyl, unless noted otherwise) synthesized from biferrocene, was photolyzed with visible light in acetonitrile in the presence of 1,2-bis(diphenylphosphino)ethane (dppe) or bis(diphenylphosphino)methane (dppm) at −15 °C to give [Fe2Fv(dppe)2(NCMe)2]2+(PF6-)2 (2a2+) or [Fe2Fv(dppm)2(NCMe)2]2+(PF6-)2 (2b2+). The complexes 2a2+ and 2b2+ reacted in refluxing 1,2-dichloroethane with CO to give [Fe2Fv(dppe)2(CO)2]2+(PF6-)2 (3a2+) and [Fe2Fv(dppm)2(CO)2]2+(PF6-)2 (3b2+), and 2a2+ reacted similarly with PMe3 to give [Fe2Fv(dppe)2(PMe3)]2+(PF6-)2 (42+). The direduced 38-electron (38e) complex 1 reacted at −15 °C with 1 atm of CO to give [Fe2(μ2-η4:η4-Fv)(CO)6] (7) and with PMe3 to give [Fe2Fv(PMe3)4] (9). When Na+PF6- was present in stoichiometric amounts in THF, these reactions followed a different course and Na+PF6- induced electron transfer (disproportionation) by irreversibly dislocating ion pairs:  the reaction of 1 with 1 atm of CO gave...

The complexes [{Fe(eta(5)-C(5)Me(5))}(2)(mu(2),eta(12)-phenanthrene)](n+) have been synthesized for n = 0-2; the green 37-electron mixed-valence (FeFeII)-Fe-I monocation is delocalized on the Mossbauer time-scale at 4 K and the bireduced neutral complex has a triplet (FeFeI)-Fe-I state for phenanthrene in contrast with the singlet (FeFeII)-Fe-II state for the dihydrophenanthrene complex; interconversion between the phenanthrene and dihydrophenanthrene series by contact with O-2 and H2O makes this system a switchable molecular-electronic device.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTElectronic Interplay between Two Iron Centers across Polyaromatic Ligands: Syntheses, Redox Chemistry, and Electronic Structures of the Electron-Reservoir 36- to 38-Electron Complexes [(FeCp*)2(.mu.2-.eta.12-polyaromatic)]q+ (q = 0-2) Including Mixed Valences and BiradicalsHassan Rabaa, Marc Lacoste, Marie-Helene Delville-Desboise, Jaime Ruiz, Bruno Gloaguen, Nicole Ardoin, Didier Astruc, Albert Le Beuze, Jean-Yves Saillard, and Cite this: Organometallics 1995, 14, 11, 5078–5092Publication Date (Print):November 1, 1995Publication History Published online1 May 2002Published inissue 1 November 1995https://pubs.acs.org/doi/10.1021/om00011a030https://doi.org/10.1021/om00011a030research-articleACS PublicationsRequest reuse permissionsArticle Views310Altmetric-Citations38LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

The Na+PF6- salt changes the course of reactions between neutral or ionic substrates. Examples of reactions include superoxide radical chemistry, disproportionation, and C-H and C-O bond activation. This special salt effect is usually quantitative and sometimes catalytic. When compared to other salts, Na+PF6- by far gives the most spectacular results, due to the small size of Na+ as compared to large organometallic cations.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSalt-induced, ligand-controlled, intra- vs intermolecular electron transfer in a fulvalene-bridged organoiron diradicalMarie Helene Delville, Marc Lacoste, and Didier AstrucCite this: J. Am. Chem. Soc. 1992, 114, 21, 8310–8311Publication Date (Print):October 1, 1992Publication History Published online1 May 2002Published inissue 1 October 1992https://pubs.acs.org/doi/10.1021/ja00047a064https://doi.org/10.1021/ja00047a064research-articleACS PublicationsRequest reuse permissionsArticle Views223Altmetric-Citations28LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInformVolume 21, Issue 41 Organoelement Compounds ChemInform Abstract: Arene Exchange by P Donors in the 19-Electron Complexes FeICp(arene): Kinetics, Mechanism, and Salt Effects. Interconversion, Radical-Type Reactions, and Electron-Transfer Chemistry of the New 17-Electron and 19-Electron Radicals FeICpLn (L: Phosphine, Phosphite; n = 2, 3). J. RUIZ, J. RUIZ Lab. Chim. Org. Organomet., CNRS, Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this authorM. LACOSTE, M. LACOSTE Lab. Chim. Org. Organomet., CNRS, Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this authorD. ASTRUC, D. ASTRUC Lab. Chim. Org. Organomet., CNRS, Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this author J. RUIZ, J. RUIZ Lab. Chim. Org. Organomet., CNRS, Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this authorM. LACOSTE, M. LACOSTE Lab. Chim. Org. Organomet., CNRS, Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this authorD. ASTRUC, D. ASTRUC Lab. Chim. Org. Organomet., CNRS, Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this author First published: October 9, 1990 https://doi.org/10.1002/chin.199041270AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume21, Issue41October 9, 1990 RelatedInformation

ChemInformVolume 21, Issue 16 Reviews ChemInform Abstract: Structural Consequences of Electron-Transfer in Dinuclear Iron Polyaromatic Complexes D. ASTRUC, D. ASTRUC Lab. Chim. Org. Organometall., Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this authorM. LACOSTE, M. LACOSTE Lab. Chim. Org. Organometall., Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this authorM. H. DESBOIS, M. H. DESBOIS Lab. Chim. Org. Organometall., Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this authorF. VARRET, F. VARRET Lab. Chim. Org. Organometall., Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this authorL. TOUPET, L. TOUPET Lab. Chim. Org. Organometall., Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this author D. ASTRUC, D. ASTRUC Lab. Chim. Org. Organometall., Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this authorM. LACOSTE, M. LACOSTE Lab. Chim. Org. Organometall., Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this authorM. H. DESBOIS, M. H. DESBOIS Lab. Chim. Org. Organometall., Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this authorF. VARRET, F. VARRET Lab. Chim. Org. Organometall., Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this authorL. TOUPET, L. TOUPET Lab. Chim. Org. Organometall., Univ. Bordeaux I, 33405 Talence, Fr.Search for more papers by this author First published: April 17, 1990 https://doi.org/10.1002/chin.199016328Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume21, Issue16April 17, 1990 RelatedInformation

The X-ray crystal structure of [(FeC5Me5)2(µ2,η10-biphenyl)]+PF6–,(1)+, shows a 37-electron configuration indicating that the two-electron transfer (1)2+(36e)→(1)+(37e)→(1)(36e) proceeds with structural reorganization and stabilization in the second electron transfer.

The reduction of [(FeCp)2(biphenyl)]2+(2a2+) was found to a chemically and electrochemically reversible two-electron process by cyclic voltammetry in DMF at -38-degrees-C. With LiAlH-4 this 2e reduction in THF at -80-degrees-C gives an ESR-silent blue species 2, unstable above -50-degrees-C, the structure of which was searched by using Cp* (Cp* = C5Me5). The 2e reduction of the new complex [(FeCp*)2(biphenyl)]2+(PF6-)2(2b2+), using Na/Hg in THF at 20-degrees-C gives the ESR-silent stable blue diamagnetic complex 2b, analogous to 2a, whereas the cyclic voltammogram of 2b2+ shows close reversible one-electron waves. The complex 2b was shown by H-1 and C-13 NMR and Mossbauer spectroscopy to have a 36e Fe2(II)bicyclohexadienylidene structure. Comproportionation (K = 172 at 20-degrees-C) was achieved by mixing 2b2+(PF6-)2 and 2b in THF at 20-degrees-C, which gives an 90% yield of the green mixed-valence complex 2b+. The latter is a 37e complex with a weak distortion of the biphenyl ligand and showed 3g values in ESR characterizing a Fe(I)Fe(II) complex. Its Mossbauer spectra at 0 field are essentially temperature independent and only contain one quadrupole doublet between 4 and 293 K with an isomer shift and a quadrupole splitting intermediate between those of Fe(I) and Fe(II) monomeric units. This indicates an average valence structure with delocalization or fast electron hopping. Under a field of 6 T, an isotropic value of -3.3 T is obtained for the saturation hyperfine tensor [A]. For the latter, an expected orbital contribution of -0.4 T, mainly representing the contact term, corresponds to 25% of the total spin density on the biphenyl ligand of 2b+. SCF-MS-X-alpha calculations on 2a2+, 2a+, and 2a show that, when 2a2+ is reduced, the first electron transfer involves a metallic b(u) level, which has come pie-cc antibonding character between the two atoms linking the phenyl rings. The second electron transfer is accompanied by a significant increase of this pi-cc antibonding character. A decreasing of the pi-cc bonding character of the highest occupied levels of a(g) symmetry is also noted. Additional calculations on 1a2+ ]Fe2-(mu-2, eta-12-fulvalene)(biphenyl)]2+ (1a2+) (isomer of 2a2+) indicate that, in contrast to the unoccupied b(u) biphenylic level of 2a2+, the corresponding fulvenic b(u) level is too high in energy to be accessible. Consistently, the reduction of 1a2+ is essentially a metal reduction, whereas the reduction of 2a2+ can be considered as only involving the biphenyl ligand. Altogether, an accurate determination of the electronic and structural transformation (including their orbital description and thermodynamic estimation) that occurs upon each ET of a fast, reversible 2e-transfer process is reported for the first time, which allows for understanding and thus designing of last 2e-transfer reagents.

Two aspects of the properties of iron sandwich complexes as molecular reservoir materials are reviewed in a prospective way: (i) electronic properties

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTComplexation of polyaromatics by C5H5Fe+ and C5Me5Fe+ and electronic structures of the monoreduced complexesMarc Lacoste, Hassan Rabaa, Didier Astruc, Albert Le Beuze, Jean Yves Saillard, Gilles Precigoux, Christian Courseille, Nicole Ardoin, and Walter BowyerCite this: Organometallics 1989, 8, 9, 2233–2242Publication Date (Print):September 1, 1989Publication History Published online1 May 2002Published inissue 1 September 1989https://pubs.acs.org/doi/10.1021/om00111a021https://doi.org/10.1021/om00111a021research-articleACS PublicationsRequest reuse permissionsArticle Views342Altmetric-Citations46LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

J. Ruiz, M. Lacoste and D. Astruc, J. Chem. Soc., Chem. Commun., 1989, 813 DOI: 10.1039/C39890000813

Organo di-iron electron reservoirs Fe(CP*)2(Ar)n+ withn=2, 1, 0, where Cp* is C5(CH3)5 and where Ar are the following bridges: biphenyl, dihydrophenanthrene, triphenylene, have been studied by Mössbauer spectroscopy in the solid state. Complexes withn=2, with 36e− in the coordination spheres of the metals, exhibit the usual diamagnetic behaviour of 18e−, FeII mono-iron systems. Complexes withn=1, 37e−, are delocalized mixed valence (FeIIFeI) with a spin 1/2; the magnetic hyperfine interaction, measured under an external field, shows equal delocalization of the 37th e− on the two iron centers and the two bridging carbon atoms of the biphenylene. Complexes withn=0, formally with 38e−, have a practically temperature-independent quadrupole splitting, and isomer shift values which constrast with the expected behaviour of independent FeI, 19e− centers. This indicates that the 37th and 38th electrons are mostly located on the polyaromatic bridge. Spectra obtained in an external field show a negligible magnetic hyperfine interaction and support this conclusion. In the case of biphenyl and dihydrophenanthrene bridges, this electron localization can be related to a strong intramolecular chemical coupling, evidenced by other spectroscopic and X-ray data [1].

Bi-iron electron reservoirs complexes, of sandwich structure, have been studied in the 36, 37, 38 e-states, by MGssbauer spectroscopy in external magnetic fields.The nature of the various couplings between the 19 e-subunits has been elucidated, and correlated to the electron transfer to the bridge in the mixed valence state.