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

Majid Shaikh; Sayyad Sultan Kasim

doi:doi:10.11648/j.ajhc.20220801.12

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

Majid Shaikh, Sayyad Sultan Kasim

Published in American Journal of Heterocyclic Chemistry (Volume 8, Issue 1)

Received: 30 August 2022 Accepted: 27 September 2022 Published: 28 October 2022

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Abstract

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.

Published in	American Journal of Heterocyclic Chemistry (Volume 8, Issue 1)
DOI	10.11648/j.ajhc.20220801.12
Page(s)	7-11
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2022. Published by Science Publishing Group

Keywords

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

References

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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. https://doi.org/10.11648/j.ajhc.20220801.12

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Majid Shaikh; Sayyad Sultan Kasim. Deep Eutectic Solvent a Highly Efficient Medium for the Synthesis of Imidazo [1, 2-a] Pyridines Having Green Chemistry Approach. Am. J. Heterocycl. Chem. 2022, 8(1), 7-11. doi: 10.11648/j.ajhc.20220801.12

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Majid Shaikh, Sayyad Sultan Kasim. Deep Eutectic Solvent a Highly Efficient Medium for the Synthesis of Imidazo [1, 2-a] Pyridines Having Green Chemistry Approach. Am J Heterocycl Chem. 2022;8(1):7-11. doi: 10.11648/j.ajhc.20220801.12

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@article{10.11648/j.ajhc.20220801.12,
  author = {Majid Shaikh and Sayyad Sultan Kasim},
  title = {Deep Eutectic Solvent a Highly Efficient Medium for the Synthesis of Imidazo [1, 2-a] Pyridines Having Green Chemistry Approach},
  journal = {American Journal of Heterocyclic Chemistry},
  volume = {8},
  number = {1},
  pages = {7-11},
  doi = {10.11648/j.ajhc.20220801.12},
  url = {https://doi.org/10.11648/j.ajhc.20220801.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajhc.20220801.12},
  abstract = {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.},
 year = {2022}
}

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TY  - JOUR
T1  - Deep Eutectic Solvent a Highly Efficient Medium for the Synthesis of Imidazo [1, 2-a] Pyridines Having Green Chemistry Approach
AU  - Majid Shaikh
AU  - Sayyad Sultan Kasim
Y1  - 2022/10/28
PY  - 2022
N1  - https://doi.org/10.11648/j.ajhc.20220801.12
DO  - 10.11648/j.ajhc.20220801.12
T2  - American Journal of Heterocyclic Chemistry
JF  - American Journal of Heterocyclic Chemistry
JO  - American Journal of Heterocyclic Chemistry
SP  - 7
EP  - 11
PB  - Science Publishing Group
SN  - 2575-5722
UR  - https://doi.org/10.11648/j.ajhc.20220801.12
AB  - 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.
VL  - 8
IS  - 1
ER  -

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Author Information

Majid Shaikh

Department of Chemistry, Maulana Azad College, Aurangabad, India
Sayyad Sultan Kasim

Department of Chemistry, Maulana Azad College, Aurangabad, India

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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. https://doi.org/10.11648/j.ajhc.20220801.12

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Majid Shaikh; Sayyad Sultan Kasim. Deep Eutectic Solvent a Highly Efficient Medium for the Synthesis of Imidazo [1, 2-a] Pyridines Having Green Chemistry Approach. Am. J. Heterocycl. Chem. 2022, 8(1), 7-11. doi: 10.11648/j.ajhc.20220801.12

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Majid Shaikh, Sayyad Sultan Kasim. Deep Eutectic Solvent a Highly Efficient Medium for the Synthesis of Imidazo [1, 2-a] Pyridines Having Green Chemistry Approach. Am J Heterocycl Chem. 2022;8(1):7-11. doi: 10.11648/j.ajhc.20220801.12

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@article{10.11648/j.ajhc.20220801.12,
  author = {Majid Shaikh and Sayyad Sultan Kasim},
  title = {Deep Eutectic Solvent a Highly Efficient Medium for the Synthesis of Imidazo [1, 2-a] Pyridines Having Green Chemistry Approach},
  journal = {American Journal of Heterocyclic Chemistry},
  volume = {8},
  number = {1},
  pages = {7-11},
  doi = {10.11648/j.ajhc.20220801.12},
  url = {https://doi.org/10.11648/j.ajhc.20220801.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajhc.20220801.12},
  abstract = {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.},
 year = {2022}
}

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TY  - JOUR
T1  - Deep Eutectic Solvent a Highly Efficient Medium for the Synthesis of Imidazo [1, 2-a] Pyridines Having Green Chemistry Approach
AU  - Majid Shaikh
AU  - Sayyad Sultan Kasim
Y1  - 2022/10/28
PY  - 2022
N1  - https://doi.org/10.11648/j.ajhc.20220801.12
DO  - 10.11648/j.ajhc.20220801.12
T2  - American Journal of Heterocyclic Chemistry
JF  - American Journal of Heterocyclic Chemistry
JO  - American Journal of Heterocyclic Chemistry
SP  - 7
EP  - 11
PB  - Science Publishing Group
SN  - 2575-5722
UR  - https://doi.org/10.11648/j.ajhc.20220801.12
AB  - 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.
VL  - 8
IS  - 1
ER  -

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