Green one-pot multicomponent synthesis of pyrrolidinones using planetary ball milling process under solvent-free conditions

Abstract

This paper presents a novel and efficient protocol for the synthesis of pyrrolidinones using catalytic loading of 1,1'-butylenebis(3-sulfo-3H-imidazol-1-ium) hydrogen sulfate as a recyclable Brönsted acid ionic liquid through ball milling process at room temperature under solvent-free conditions. The developed method provides good to excellent yields of various pyrrolidinones in environmentally friendly conditions. Furthermore, this efficient protocol displays a combination of the synthetic advantage of one-pot multicomponent reaction with ecological benefits and convenience of a mechanochemical procedure.

Graphical Abstract

KEYWORDS:

• Mechanochemistry
• pyrrolidinone
• ionic liquid
• Brönsted acid
• eco-friendly conditions

Acknowledgments

The authors are grateful to staff members in the Analytical and Testing Center of Malaya University for partial support. The authors received no specific funding for this research.

Disclosure statement

There are no conflicts of interest to declare.

Supporting information

Full experimental detail along with yield, melting point, ¹H and ¹³C NMR spectra, elemental analysis data, and ¹H NMR and ¹³C NMR copies of 4a, 4d, 4 g, 4 l, 4 m, 4n, and 4o can be found via the “Supplementary Content” section of this article’s webpage.