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Deep Eutectic Solvent a Highly Efficient Medium for the Synthesis of Imidazo [1, 2-a] Pyridines Having Green Chemistry Approach

The imidazo [1, 2-a] pyridine is valuable structural unit in the area of natural products and pharmaceuticals. Extremely effective one pot method developed for the production of imidazo [1, 2-a] pyridines. The reaction of N-bromosuccinimide, acetophenones and 2-aminopyridines in deep eutectic solvent and reaction completed within a minute. The most remarkable features of such reaction is lowest minimum time, high atom, mild reaction condition and step economy. Methods The mixture of substituted acetophenones, N-bromosuccinimide in deep eutectic solvent as a green medium and 2-aminopyridines. The optimization of the reaction conditions with regard to their chemo selectivity of deep eutectic solvent. An imidazopyridine is a nitrogen containing heterocycle which plays crucial role in medicinal and pharmacological chemistry. Results To synthesize the imidazo [1, 2-a] pyridines, In the deep eutectic solvents add N-bromosuccinimide, acetophenones at room temperature immediately reaction completed within a minute, TLC Shows single spot which indicate that formation of α- bromoketones. On formation of α- bromoketones; 2-aminopyridine was added in the reaction mass after completion of reaction, the reaction mixture was poured in ice-cold water; the solid product obtained was filtered. Conclusion The main remarkable characteristics of this protocol such as no need to isolate lachrymatric α-bromoketones, clean reaction profile, mild reaction condition, require minimum reaction time, inexpensive and green aspects such as avoid hazardous solvents, poisonous catalyst, higher yield and ease of work-up.

Deep Eutectic Solvent, Imidazol-Pyridine, Acetophenones, 2-Aminopyridines

Majid Shaikh, Sayyad Sultan Kasim. (2022). Deep Eutectic Solvent a Highly Efficient Medium for the Synthesis of Imidazo [1, 2-a] Pyridines Having Green Chemistry Approach. American Journal of Heterocyclic Chemistry, 8(1), 7-11.

Copyright © 2022 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License ( which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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