Three Generations of Cobalt Porphyrins as Catalysts in the Oxidation of Cycloalkanes.
ChemSusChem
; 12(3): 684-691, 2019 Feb 07.
Article
em En
| MEDLINE
| ID: mdl-30426703
ABSTRACT
Three generations of cobalt porphyrins were synthesized, physicochemically characterized by FTIR and UV/Vis spectroscopy as well as cyclic voltammetry and applied as catalysts in the oxidation of cycloalkanes with atmospheric molecular oxygen under mild conditions. All examined catalysts were active in the tested reaction, and their catalytic activity varied with the nature and number of substituents on the porphyrin ring. Introduction of electron-withdrawing or electron-donating substituents at the porphyrin rings increases the activity of metalloporphyrin complexes. It was found, for the first time, that generationâ
II cobalt porphyrins show higher activity in cycloalkane oxidation than cobalt porphyrins of generationâ
III. The lower catalytic activity of generationâ
III cobalt porphyrins can be attributed to the saddle-shaped deformation of the porphyrin macrocycle. DFT modeling of Co porphyrins and their interactions with molecular oxygen provided explanations for the observed effects. On the basis of prior reports and the obtained results, a reaction mechanism is proposed and discussed.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
ChemSusChem
Assunto da revista:
QUIMICA
/
TOXICOLOGIA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Polônia