Solvent-free C-3 coupling of azaindoles with cyclic imines

Khadija Belasri, F. Fülöp, I. Szatmári

Research output: Contribution to journalArticle

Abstract

By direct coupling 7-azaindole and cyclic imines, such as 3,4-dihydroisoquinoline, 6,7-dihydrothieno[3,2-c]pyridine, 3,4-dihydro-β-carboline, and 4,5-dihydro-3H-benz[c]azepine, new 3-substituted 7-azaindole derivatives have been synthesized. The reaction was extended to 4-azaindoles and 6-azaindoles, as electron-rich aromatic compounds. The lowest reactivity was observed in the case of C-3 substitution of 5-azaindole. In this case, the aza-Friedel-Crafts reaction took place by using 10 mol % of p-toluenesulfonic acid (p-TSA) as the catalyst. The role of the acid catalyst can be explained by the different pKa values of the azaindoles. All reactions were performed in solvent-free conditions by using both classical heating and microwave irradiation. In all cases, microwave heating proved to be more convenient to synthesize new C-3-substituted azaindole derivatives.

Original languageEnglish
Article number3578
JournalMolecules
Volume24
Issue number19
DOIs
Publication statusPublished - Oct 4 2019

Fingerprint

Imines
Microwaves
Heating
imines
Azepines
Friedel-Craft reaction
Friedel-Crafts reaction
Derivatives
microwaves
catalysts
Carbolines
acids
Catalysts
heating
Microwave heating
Microwave irradiation
aromatic compounds
Aromatic compounds
pyridines
Substitution reactions

Keywords

  • 4-azaindole
  • 5-azaindole
  • 6-azaindole
  • 7-azaindole
  • Aza-Friedel-Crafts reaction
  • Cyclic imines
  • Microwave reaction

ASJC Scopus subject areas

  • Analytical Chemistry
  • Chemistry (miscellaneous)
  • Molecular Medicine
  • Pharmaceutical Science
  • Drug Discovery
  • Physical and Theoretical Chemistry
  • Organic Chemistry

Cite this

Solvent-free C-3 coupling of azaindoles with cyclic imines. / Belasri, Khadija; Fülöp, F.; Szatmári, I.

In: Molecules, Vol. 24, No. 19, 3578, 04.10.2019.

Research output: Contribution to journalArticle

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