SOMC-Designed Silica Supported Tungsten Oxo Imidazolin-2-iminato Methyl Precatalyst for Olefin Metathesis Reactions.

Title SOMC-Designed Silica Supported Tungsten Oxo Imidazolin-2-iminato Methyl Precatalyst for Olefin Metathesis Reactions.
Authors Z.S. Qureshi; A. Hamieh; S. Barman; N. Maity; M.K. Samantaray; S. Ould-Chikh; E. Abou-Hamad; L. Falivene; V. D'Elia; A. Rothenberger; I. Llorens; J.L. Hazemann; J.M. Basset
Journal Inorg Chem
DOI 10.1021/acs.inorgchem.6b02424
Abstract

Synthesis, structure, and olefin metathesis activity of a surface complex [(?Si-O-)W(?O)(CH3)2-Im(Dipp)N] (4) (Im(Dipp) = 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-iminato) supported on silica by a surface organometallic chemistry (SOMC) approach are reported. The reaction of N-silylated 2-iminoimidazoline with tungsten(VI) oxytetrachloride generated the tungsten oxo imidazolin-2-iminato chloride complex [Im(Dipp)NW(?O)Cl3] (2). This was grafted on partially dehydroxylated silica pretreated at 700 °C (SiO2-700) to afford a well-defined monopodal surface complex [(?Si-O-)W(?O)Cl2-Im(Dipp)N] (3). 3 underwent alkylation by ZnMe2 to produce [(?Si-O-)W(?O)(CH3)2-Im(Dipp)N] (4). The alkylated surface complex was thoroughly characterized by solid-state NMR, elemental microanalysis, Raman, FT-IR spectroscopies, and XAS analysis. 4 proved to be an active precatalyst for self-metathesis of terminal olefins such as propylene and 1-hexene.

Citation Z.S. Qureshi; A. Hamieh; S. Barman; N. Maity; M.K. Samantaray; S. Ould-Chikh; E. Abou-Hamad; L. Falivene; V. D'Elia; A. Rothenberger; I. Llorens; J.L. Hazemann; J.M. Basset.SOMC-Designed Silica Supported Tungsten Oxo Imidazolin-2-iminato Methyl Precatalyst for Olefin Metathesis Reactions.. Inorg Chem. 2017;56(2):861871. doi:10.1021/acs.inorgchem.6b02424

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