α-Halogenoacetanilides as hydrogen-bonding organocatalysts that activate carbonyl bonds: fluorine versus chlorine and bromine.
Chemistry
; 20(10): 2849-59, 2014 Mar 03.
Article
em En
| MEDLINE
| ID: mdl-24519659
ABSTRACT
α-Halogenoacetanilides (X=F, Cl, Br) were examined as H-bonding organocatalysts designed for the double activation of CO bonds through NH and CH donor groups. Depending on the halide substituents, the double H-bond involved a nonconventional CHâ
â
â
O interaction with either a HCXn (n=1-2, X=Cl, Br) or a HCAr bond (X=F), as shown in the solid-state crystal structures and by molecular modeling. In addition, the catalytic properties of α-halogenoacetanilides were evaluated in the ring-opening polymerization of lactide, in the presence of a tertiary amine as cocatalyst. The α-dichloro- and α-dibromoacetanilides containing electron-deficient aromatic groups afforded the most attractive double H-bonding properties towards CO bonds, with a NHâ
â
â
Oâ
â
â
HCX2 interaction.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Bromo
/
Cloro
/
Fluoretos
/
Flúor
/
Hidrocarbonetos Halogenados
/
Acetanilidas
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article