A Practical and Highly Efficient Synthesis of 1,2,4,5-Tetrasubstituted Imidazoles Using 2-Ethylhexanoic acid as a Reusable Organocatalyst and Reaction Medium
2-Ethylhexanoic acid has been applied as a dual solvent-catalyst for the one-pot, four-component synthesis of 1,2,4,5-tetrasubstituted imidazoles. This naturally occurring and widely produced fatty acid exhibited remarkable catalytic activity and was easily separated by extraction. The reusability of this catalytic media was examined up to four times and no significant drop in catalytic activity was observed. Utilizing ecofriendly, low cost and commercially available reagent, short reaction times (30-90 min), very good to excellent yields (88-93) and straightforward workup procedure are the salient properties offered by this methodology.
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