Next Article in Journal
Effect of the Algicide Thiazolidinedione 49 on Immune Responses of Bay Scallop Argopecten Irradians
Next Article in Special Issue
Synthesis, Structure and In Vitro Cytotoxic Activity of Novel Cinchona—Chalcone Hybrids with 1,4-Disubstituted- and 1,5-Disubstituted 1,2,3-Triazole Linkers
Previous Article in Journal
Line Scan Raman Microspectroscopy for Label-Free Diagnosis of Human Pituitary Biopsies
Open AccessArticle

Solvent-Free C-3 Coupling of Azaindoles with Cyclic Imines

1
Institute of Pharmaceutical Chemistry and MTA-SZTE Stereochemistry Research Group, University of Szeged, H-6720 Szeged, Hungary
2
Institute of Pharmaceutical Chemistry, Interdisciplinary Centre of Excellence, University of Szeged, H-6720 Szeged, Hungary
*
Author to whom correspondence should be addressed.
Academic Editor: Antal Csámpai
Molecules 2019, 24(19), 3578; https://doi.org/10.3390/molecules24193578
Received: 3 September 2019 / Revised: 26 September 2019 / Accepted: 2 October 2019 / Published: 4 October 2019
(This article belongs to the Special Issue Synthesis and Structure of Heterocyclic and Organometallic Compounds)
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. View Full-Text
Keywords: cyclic imines; 7-azaindole; 6-azaindole; 4-azaindole; 5-azaindole; aza-Friedel-Crafts reaction; microwave reaction cyclic imines; 7-azaindole; 6-azaindole; 4-azaindole; 5-azaindole; aza-Friedel-Crafts reaction; microwave reaction
Show Figures

Graphical abstract

MDPI and ACS Style

Belasri, K.; Fülöp, F.; Szatmári, I. Solvent-Free C-3 Coupling of Azaindoles with Cyclic Imines. Molecules 2019, 24, 3578.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop