Unearthing a Well-Defined Highly Active Bimetallic W/Ti Precatalyst Anchored on a Single Silica Surface for Metathesis of Propane.
Two compatible organometallic complexes, W(Me) (1) and TiNp (2), were successively anchored on a highly dehydroxylated single silica support (SiO) to synthesize the well-defined bimetallic precatalyst [(?Si-O-)W(Me)(?Si-O-)Ti(Np)] (4). Precatalyst 4 was characterized at the molecular level using adv...
| Publicado en: | Journal of the American Chemical Society Vol. 139; no. 9; pp. 3522 - 3528 |
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| Autores principales: | , , , , , , |
| Formato: | Resumen |
| Publicado: |
American Chemical Society
3/8/2017
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| Materias: | |
| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=121727874&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 121727874 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 3/8/2017 vid: 139 iid: 9 pid: 997 pub: American Chemical Society artinfo: ui: 121727874 10.1021/jacs.6b12970 ppf: 3522 ppct: 6 formats: tig: atl: Unearthing a Well-Defined Highly Active Bimetallic W/Ti Precatalyst Anchored on a Single Silica Surface for Metathesis of Propane. aug: au: Samantaray, Manoja K. Kavitake, Santosh Morlanés, Natalia Abou-Hamad, Edy Hamieh, Ali Dey, Raju Basset, Jean-Marie affil: King Abdullah University of Science and Technology, KAUST Catalysis Center (KCC), Thuwal 23955-6900, Saudi Arabia su: Metals Propane Silica sug: subj: Metals Propane Silica ab: Two compatible organometallic complexes, W(Me) (1) and TiNp (2), were successively anchored on a highly dehydroxylated single silica support (SiO) to synthesize the well-defined bimetallic precatalyst [(?Si-O-)W(Me)(?Si-O-)Ti(Np)] (4). Precatalyst 4 was characterized at the molecular level using advanced surface organometallic chemistry (SOMC) characterization techniques. The strong autocorrelation observed between methyl of W and Ti in H-H multiple-quantum NMR spectra demonstrates that W and Ti species are in close proximity to each other. The bimetallic precatalyst 4, with a turnover number (TON) of 9784, proved to be significantly more efficient than the silica-supported monometallic catalyst [(?Si-O-)W(Me)] (3), with a TON of 98, for propane metathesis at 150 °C in a flow reactor. The dramatic improvement in the activity signifies the cooperativity between Ti and W and indicates that the key step of alkane metathesis (C-H bond activation followed by β-H elimination) occurs on Ti, followed by olefin metathesis, which occurs on W. We have demonstrated the influence and importance of proximity of Ti to W for achieving such a significantly high activity. This is the first report demonstrating the considerably high activity (TON = 9784) in propane metathesis at moderate temperature (150 °C) using a well-defined bimetallic system prepared via the SOMC approach. pubtype: Academic Journal doctype: Abstract src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2017 holdings: @attributes: islocal: N |
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