TITLE:
Solvent Free One-Pot Synthesis of 1,2,4,5-Tetrasubstituted Imidazoles Catalyzed by Secondary Amine Based Ionic Liquid and Defective Keggin Heteropoly Acid
AUTHORS:
Pranab Jyoti Das, Jupitara Das, Munni Ghosh, Sabera Sultana
KEYWORDS:
Ionic Liquids; Keggin Heteropolyacid; Microwave; Tetrasubstituted Imidazole; Solvent Free Synthesis; Multicomponent Reaction
JOURNAL NAME:
Green and Sustainable Chemistry,
Vol.3 No.4A,
November
22,
2013
ABSTRACT: Secondary amine based ionic liquid and defective Keggin type
heteropoly acid (HPA) are separately used for efficient one-pot four-component
synthesis of 1,2,4,5-tetrasubstituted imidazoles assisted by microwave (MW).
Eco-friendly solvent free procedure, short reaction time, high yield of
products and reusability of catalysts are important features of the synthesis.
A comparative study on the efficiency of the two catalysts is reported. This
work further demonstrates the alternate use of urea, instead of often used
ammonium acetate, as source of nitrogen.