☆ 4.8 Article

Reversible 1,2-Alkyl Migration to Carbene and Ammonia Activation in an N-Heterocyclic Carbene-Zirconium Complex

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY (2015)

Journal

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY

Volume 137, Issue 33, Pages 10500-10503

Publisher

AMER CHEMICAL SOC

DOI: 10.1021/jacs.5b06695

Keywords

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Categories

Chemistry, Multidisciplinary

Funding

U.S. DOE, Office of Basic Energy Sciences [DE-FG03-85ER13431]
NSF CRIF:MU [CHE-0639094]

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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-carbene atom. This process may be reversed, resulting in C-sp(3)-C-sp(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.

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