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Ni-X bonds

The broken bonds (boldface = dissociated fragment) BDEs (boldface = recommended data reference in parentheses) Methods (reference in References [Pg.904]

The mechanism of the reaction may involve a cationic nickel hydride associated with a weakly coordinated counterion (4, Scheme 1) as the true catalyst. This species is formed by the Lewis acid-assisted dissociation of the Ni-X bond from the 16-electron phosphine complex 3, coordination of ethylene (or styrene), coupling of the allyl and vinyl moieties, and subsequent 3-hydride elimination [11a]. Insertion of the vinylarene into the Ni-H bond gives a benzylic complex 5, which can be stabilized as an rj -intermediate 5. The coordinately unsaturated 5 can react with ethylene (and possibly not another vinylarene, if the phosphine is sufficiently bulky) to give 6, which can undergo an insertion followed by P-hydride... [Pg.406]

Ni-Cp interactions of the ligand trans-in [ucnQc exerted by the other auxiliary ligands has been discussed and the following approximate /r< //i -influence order has been suggested alkyl, hydride > phosphine, methoxide > arylamide, aryloxide, arylthiolate, bromide. A study of the Ni-amido derivatives with Bronsted acids HX has led to the observation that the Ni-X bonds have a significant electrostatic component. [Pg.167]

See other pages where Ni-X bonds is mentioned: [Pg.276]    [Pg.203]    [Pg.2911]    [Pg.1178]    [Pg.903]    [Pg.903]    [Pg.903]    [Pg.904]    [Pg.906]    [Pg.908]    [Pg.910]    [Pg.912]    [Pg.914]    [Pg.916]    [Pg.918]    [Pg.920]    [Pg.921]    [Pg.921]    [Pg.922]    [Pg.924]    [Pg.926]    [Pg.928]    [Pg.930]    [Pg.931]    [Pg.931]    [Pg.2910]    [Pg.385]   


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X-bonds

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