Redox non-innocence of a N-heterocyclic nitrenium cation bound to a nickel-cyclam core.
J Am Chem Soc
; 136(2): 582-5, 2014 Jan 15.
Article
em En
| MEDLINE
| ID: mdl-24380589
The redox properties of Ni complexes bound to a new ligand, [DMC-nit](+), where a N-heterocyclic nitrenium group is anchored on a 1,4,8,11-tetraazacyclotetradecane backbone, have been examined using spectroscopic and DFT methods. Ligand-based [(DMC-nit)Ni](2+/+) reduction and metal-based [(DMC-nit)Ni](2+/3+) oxidation processes have been established for the [(DMC-nit)Ni](+/2+/3+) redox series, which represents the first examples of nitrenium nitrogen (N(nit))-bound first-row transition-metal complexes. An unprecedented bent binding mode of N(nit) in [(DMC-nit)Ni](2+) is observed, which possibly results from the absence of any N(nit)âNi σ-donation. For the corresponding [(DMC-nit)Ni(F)](2+) complex, σ-donation is dominant, and hence a coplanar arrangement at N(nit) is predicted by DFT. The binding of the triazolium ion to Ni enables new chemistry (formate oxidation) that is not observed in a derivative that lacks this functional group. Thus the N-heterocyclic nitrenium ligand is a potentially useful and versatile reagent in transition-metal-based catalysis.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Compostos Organometálicos
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Compostos Heterocíclicos
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Níquel
/
Nitrogênio
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article