title: Reversible 1,2-Alkyl Migration to Carbene and Ammonia Activation in an N-Heterocyclic Carbene-Zirconium Complex.
abstract: Addition of trimethylphosphine to a bis(phenolate)benzylimidazolylidene(dibenzyl)zirconium complex induces migration of a benzyl ligand from the metal center to the C(carbine) atom. This process may be reversed, resulting in Csp(3)-Csp(3) activation, by abstraction of the phosphine, an example of regulated, reversible alkyl migration. Addition of ammonia to the dibenzyl complex results in migration of one benzyl group and protonolysis of the other to generate a bis(NH2)-bridged dimer via an NMR-observable intermediate NH3 adduct.
authors.affiliation: Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology , Pasadena, California 91125, United States.
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Despagnet-Ayoub
authors.affiliation: Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology , Pasadena, California 91125, United States.
authors.forename: Michael K
authors.initials: MK
authors.lastname: Takase
authors.affiliation: Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology , Pasadena, California 91125, United States.
authors.forename: Jay A
authors.initials: JA
authors.lastname: Labinger
authors.affiliation: Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology , Pasadena, California 91125, United States.
authors.forename: John E
authors.initials: JE
authors.lastname: Bercaw