title: Synergy between Two Metal Catalysts: A Highly Active Silica-Supported Bimetallic W/Zr Catalyst for Metathesis of n-Decane.
abstract: A well-defined, silica-supported bimetallic precatalyst [≡Si-O-W(Me)5≡Si-O-Zr(Np)3] (4) has been synthesized for the first time by successively grafting two organometallic complexes [W(Me)6 (1) followed by ZrNp4 (2)] on a single silica support. Surprisingly, multiple-quantum NMR characterization demonstrates that W and Zr species are in close proximity to each other. Hydrogenation of this bimetallic catalyst at room temperature showed the easy formation of zirconium hydride, probably facilitated by tungsten hydride which was formed at this temperature. This bimetallic W/Zr hydride precatalyst proved to be more efficient (TON = 1436) than the monometallic W hydride (TON = 650) in the metathesis of n-decane at 150 °C. This synergy between Zr and W suggests that the slow step of alkane metathesis is the C-H bond activation that occurs on Zr. The produced olefin resulting from a β-H elimination undergoes easy metathesis on W.
authors.affiliation: King Abdullah University of Science & Technology , KAUST Catalysis Center (KCC), 23955-6900 Thuwal, Saudi Arabia.
authors.forename: Manoja K
authors.initials: MK
authors.lastname: Samantaray
authors.affiliation: King Abdullah University of Science & Technology , KAUST Catalysis Center (KCC), 23955-6900 Thuwal, Saudi Arabia.
authors.forename: Raju
authors.initials: R
authors.lastname: Dey
authors.affiliation: King Abdullah University of Science & Technology , KAUST Catalysis Center (KCC), 23955-6900 Thuwal, Saudi Arabia.
authors.forename: Santosh
authors.initials: S
authors.lastname: Kavitake
authors.affiliation: King Abdullah University of Science & Technology , KAUST Catalysis Center (KCC), 23955-6900 Thuwal, Saudi Arabia.
authors.forename: Edy
authors.initials: E
authors.lastname: Abou-Hamad
authors.affiliation: King Abdullah University of Science & Technology , KAUST Catalysis Center (KCC), 23955-6900 Thuwal, Saudi Arabia.
authors.forename: Anissa
authors.initials: A
authors.lastname: Bendjeriou-Sedjerari
authors.affiliation: King Abdullah University of Science & Technology , KAUST Catalysis Center (KCC), 23955-6900 Thuwal, Saudi Arabia.
authors.forename: Ali
authors.initials: A
authors.lastname: Hamieh
authors.affiliation: King Abdullah University of Science & Technology , KAUST Catalysis Center (KCC), 23955-6900 Thuwal, Saudi Arabia.
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Basset