Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.



Immobilized piperazine on the surface of graphene oxide as a heterogeneous bifunctional acid–base catalyst for the multicomponent synthesis of 2-amino-3-cyano-4H-chromenes

Author affiliations

Abstract

Immobilized piperazine on the surface of graphene oxide (piperazine-GO) is synthesized and characterized by different methods such as FT-IR, solid-state 29Si{1H} and 13C{1H} CP/MAS NMR, elemental analysis, TGA, TEM, FE-SEM, XPS, and TPD. Subsequently, it is used as a heterogeneous bifunctional acid–base catalyst for the efficient multicomponent reaction of malononitrile, different active compounds containing enolizable C–H bonds and various aryl/alkyl aldehydes in aqueous ethanol. A wide variety of 2-amino-3-cyano-4H-chromenes are synthesized in the presence of this heterogeneous catalyst in good to high yields and with short reaction times. The catalyst is easily separated and reused for at least six times without significant loss of activity. The acidic nature of GO improves the catalytic activity of the supported piperazine and also provides heterogeneity to the catalyst. Use of aqueous ethanol as a green solvent, high turnover numbers (TON), facile catalyst recovery and reuse, simple work-up and generality of the method make this protocol an environmentally benign procedure for the synthesis of the title heterocycles.

Graphical abstract: Immobilized piperazine on the surface of graphene oxide as a heterogeneous bifunctional acid–base catalyst for the multicomponent synthesis of 2-amino-3-cyano-4H-chromenes

Back to tab navigation

Supplementary files

Article information


Submitted
10 Apr 2020
Accepted
22 Jun 2020
First published
22 Jun 2020

Green Chem., 2020, Advance Article
Article type
Paper

Immobilized piperazine on the surface of graphene oxide as a heterogeneous bifunctional acid–base catalyst for the multicomponent synthesis of 2-amino-3-cyano-4H-chromenes

A. Khazaee, R. Jahanshahi, S. Sobhani, J. Skibsted and J. M. Sansano, Green Chem., 2020, Advance Article , DOI: 10.1039/D0GC01274B

Social activity

Search articles by author

Spotlight

Advertisements