C-H Activation by Isolable Cationic Bis(phosphine) Cobalt(III) Metallacycles.
J Am Chem Soc
; 144(41): 19186-19195, 2022 10 19.
Article
em En
| MEDLINE
| ID: mdl-36194198
ABSTRACT
Five- and six-coordinate cationic bis(phosphine) cobalt(III) metallacycle complexes were synthesized with the general structures, [(depe)Co(cycloneophyl)(L)(L')][BArF4] (depe = 1,2-bis(diethylphosphino)ethane; cycloneophyl = [κ-CC-(CH2C(Me)2)C6H4]; L/L' = pyridine, pivalonitrile, or the vacant site, BAr4F = B[(3,5-(CF3)2)C6H3]4). Each of these compounds promoted facile directed C(sp2)-H activation with exclusive selectivity for ortho-alkylated products, consistent with the selectivity of reported cobalt-catalyzed arene-alkene-alkyne coupling reactions. The direct observation of C-H activation by cobalt(III) metallacycles provided experimental support for the intermediacy of these compounds in this class of catalytic C-H functionalization reaction. Deuterium labeling and kinetic studies provided insight into the nature of C-H bond cleavage and C-C bond reductive elimination from isolable cobalt(III) precursors.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Piridinas
/
Cobalto
Idioma:
En
Revista:
J Am Chem Soc
Ano de publicação:
2022
Tipo de documento:
Article