000028737 001__ 28737
000028737 005__ 20130211180554.0
000028737 0247_ $$2urn$$aurn:nbn:ch:rero-004-110686
000028737 0248_ $$aoai:doc.rero.ch:20120312113727-GT$$pthesis$$pthesis_urn$$zcdu34$$zreport$$zbook$$zcdu54$$zjournal$$zcdu16$$zpostprint$$zpreprint$$zcdu1$$zdissertation$$zunine
000028737 035__ $$aR007018691
000028737 041__ $$aeng
000028737 080__ $$a54
000028737 100__ $$aKhan, Farooq-Ahmad
000028737 245__ $$9eng$$aMetallic ruthenium nanoparticles derived from arene ruthenium complexes$$bsynthesis, characterization and applications
000028737 300__ $$a135
000028737 502__ $$92012$$aThèse de doctorat : Université de Neuchâtel, 2012 ; 2247
000028737 506__ $$ffree
000028737 520__ $$9eng$$a<br> The present work deals with the preparation of ruthenium nanoparticles using an organometallic approach. In the first part, the synthesis of ruthenium nanoparticles stabilized by mesogenic isonicotinic ester ligands is presented. We have been interested in the use of long-chain isonicotinic esters as lipohilic components in order to increase the anticancer activity of arene ruthenium complexes, while using them as stabilizers for ruthenium nanoparticles with the aim of exploring self-organization and biological (anticancer) properties of these new hybrid materials. The ruthenium nanoparticles thus obtained as well as their organometallic precursors showed anticancer activity comparable to cisplatin or superior to cisplatin in the cancer cell lines A2780 and cisplatin-resistant cell line A2780cisR, the highest cytotoxicity being 0.179 µM, a value 9 fold lower than cisplatin – a platinum-based chemotherapy drug widely used to treat different types of cancers. <br><br> In second part, silicate-supported ruthenium nanoparticles with a special emphasis on hectorite-supported Ru(0) is presented. Size- and shape-selective preparation of hectorite-supported ruthenium nanoparticles was achieved by using either molecular hydrogen or solvothermal reduction route employing different organometallic precursors. The catalytic efficiency of these nanoparticles was evaluated for different arenes, furfuryl alcohol and α,β-unsaturated ketones. Hectorite-supported ruthenium nanoparticles were found to be promising hydrogenation catalysts. It was observed that the modification of intercalated particles size and reaction conditions tune the catalytic activity for chemo-selective reactions. Thus, these nanoparticles preferentially reduce the C=C olefinic bond in α,β-unsaturated ketones at 35 °C. However, change in particle size results in high selectivity towards C=O bond of α,β-unsaturated ketones, if an excess of solvent is used at low temperatures. A selectivity > 98 % for an unconstrained α,β-unsaturated ketone, <i>trans</i>-4-phenyl-3-penten-2-one, was observed at 0 °C. This kind of selectivity is unique for a heterogeneous catalyst especially when the C=C olefinic bond in α, β-unsaturated moiety is sterically not hindered. It was believed that such a preferential C=O bond hydrogenation in α,β-unsaturated ketones was not possible with heterogeneous catalysts.  <br><br> In the last part, superparamagnetic core-shell-type Fe<sub>3</sub>O<sub>4</sub>/Ru nanoparticles (particle size ~ 15 nm), synthesized by co-precipitation, adsorption and reduction methods, are presented. Their catalytic efficiency for selective C=O hydrogenation in an unconstrained α,β-unsaturated ketone was evaluated using <>trans</i>-4-phenyl-3-penten-2-one. These particles present a green and sustainable approach towards catalyst separation from the reaction mixture, as they can be efficiently separated from the reaction mixture by applying an external magnetic field. <br><br> It was the aim of this study to develop metallic ruthenium nanoparticles stabilized by mesogenic isonicotinic ester ligands, intercalated in hectorite and supported on magnetite and to evaluate their catalytic and biological potential.
000028737 695__ $$9fre$$aNanoparticules de Ruthénium ; activité anti-cancéreuse ; complexes arène-ruthénium ; nanoparticules supportées ; nanoparticules superparamagnétiques ; les nanoparticules de type core-shell ; l'hydrogénation catalytique ; l'hydrogénation sélective
000028737 695__ $$9eng$$aRuthenium nanoparticles ; anticancer activity ; arene ruthenium complexes ; supported nanoparticles ; superparamagnetic nanoparticles ; core-shell type nanoparticles ; catalytic hydrogenation ; selective hydrogenation
000028737 700__ $$aSüss-Fink, Georg$$eDir.
000028737 8564_ $$fKhan_Farooq-Ahmad_-_Metallic_Ruthenium_Nanoparticles_Derived_from_Arene_Ruthenium_Complexes._THESE_UNINE_2247_2011.pdf$$qapplication/pdf$$s7904785$$uhttp://doc.rero.ch/record/28737/files/Khan_Farooq-Ahmad_-_Metallic_Ruthenium_Nanoparticles_Derived_from_Arene_Ruthenium_Complexes._THESE_UNINE_2247_2011.pdf$$yorder:1$$zTexte intégral
000028737 918__ $$aFaculté des sciences$$bRue Emile-Argand 11, 2007 Neuchâtel$$cInstitut de chimie
000028737 919__ $$aUniversité de Neuchâtel$$bNeuchâtel$$ddoc.support@rero.ch
000028737 980__ $$aTHESIS$$bUNINE$$fTH_PHD
000028737 990__ $$a20120312113727-GT