Stereoselective 1,2-cis Furanosylations Catalyzed by Phenanthroline.
J Am Chem Soc
; 144(16): 7441-7456, 2022 04 27.
Article
em En
| MEDLINE
| ID: mdl-35413194
ABSTRACT
Stereoselective formation of the 1,2-cis furanosidic linkage, a motif of many biologically relevant oligosaccharides and polysaccharides, remains an important synthetic challenge. We herein report a new stereoselective 1,2-cis furanosylation method promoted by phenanthroline catalysts under mild and operationally simple conditions. NMR experiments and density functional theory calculations support an associative mechanism in which the rate-determining step occurs from an inverted displacement of the faster-reacting phenanthrolinium ion intermediate with an alcohol nucleophile. The phenanthroline catalysis system is applicable to a number of furanosyl bromide donors to provide the challenging 1,2-cis substitution products in good yield with high anomeric selectivities. While arabinofuranosyl bromide provides ß-1,2-cis products, xylo- and ribofuranosyl bromides favor α-1,2-cis products.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fenantrolinas
/
Brometos
Idioma:
En
Revista:
J Am Chem Soc
Ano de publicação:
2022
Tipo de documento:
Article