InCl₃-Promoted Synthesis of Pyrazolyl-Substituted Quinolines in Green Media

Abstract

A series of regioisomers of pyrazolyl-substituted quinolines has been synthesized through the simple condensation reaction between hydrazinylquinolines with aliphatic 1,3-diketones with InCl₃ as a catalyst under microwave irradiation. This method produces pure products in good yield in a rapid manner compared to conventional procedures and withneat reaction condition. The approach has the advantages of operational simplicity and increased safety for a shortened synthesis of pyrazolyl-substituted quinolines.

GRAPHICAL ABSTRACT

Keywords:

• Green synthesis
• hydrazinylquinolines
• pyrazolyl-substituted quinolines
• regioisomers

ACKNOWLEDGMENTS

Our sincere thanks go to VIT-SIF Laboratory, SAS, Chemistry division, VIT University, Vellore, and SAIF, IIT Madras, Chennai, for providing access to their NMR spectral facilities.

SUPPLEMENTAL MATERIAL

General procedure and spectral data of all the compounds associated with this article are available as supporting information, which can be accessed on the publisher’s website. The cif files for compounds 2b and 3b have been deposited with the Cambridge Crystallographic Data Centre as CCDC numbers 974280 and 974279. Copies of the data can be obtained, free of charge, on application to CCDC, 12 Union Road, Cambridge, CB2 1EZ, UK [fax: [phone] or e-mail: [email protected]].