Iron(0) tricarbonyl η4-1-azadiene complexes and their catalytic performance in the hydroboration of ketones, aldehydes and aldimines via a non-iron hydride pathway.
Dalton Trans
; 51(30): 11558-11566, 2022 Aug 02.
Article
em En
| MEDLINE
| ID: mdl-35848404
ABSTRACT
Six iron(0) tricarbonyl complexes (1a-f) with a η4-1-azadiene moiety were prepared and their performance in the hydroboration of unsaturated organic compounds was investigated. All the complexes exhibit catalytic activity towards hydroboration of ketones, aldehydes and aldimines with pinacolborane (HBpin) as a hydride source to lead to secondary alcohols, primary alcohols, and secondary amines, respectively, after hydrolysis of the hydroboration products. Of the iron(0) tricarbonyl complexes, complex 1e is the most robust one and was employed throughout the catalytic investigation. Its preference towards the three types of substrates is as follows aldimines > aldehydes ⫠ketones. In total, 24 substrates were examined for the catalytic hydroboration reactivity and generally, isolation yields ranging from 40% to 95% were achieved. Mechanistic investigation suggests that the catalytic hydroboration of the substrates proceeds via intramolecular hydride transfer without going through an Fe-H intermediate. As indicated by 1H NMR spectroscopic monitoring, the substrates and the borane agent bind to the iron centre and the imine N atom, respectively, which facilitates the hydride transfer by activating the B-H bond and polarizing the double bond of the substrates.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Boranos
/
Aldeídos
Idioma:
En
Revista:
Dalton Trans
Assunto da revista:
QUIMICA
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
China