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Free Radical in Chemistry and Biology Practice

“Benzimidazoles and their derivatives, which have good biological activities and reactive activities, are very useful intermediates for the development of molecules on pharmaceutical or biological interest [21-24]. The proton transfer behavior of 2-substituted benzimidazole compounds has been an interesting topic for years [25-30]. Especially, the hydrogen bond of these compounds is close to the length of the low-barrier hydrogen bond (LBHB) [31,32]. Which will help to study the interrelation between the barrier and the p-electron delocalization.”

References

Peng, H., Huang, P., Yi, P., Xu, F., & Sun, L. (2018). Theoretical studies of π-electron delocalization and localization on intramolecular proton transfer in the ground state. Journal of Molecular Structure, 1154, 590-595.https://doi.org/10.1016/j.molstruc.2017.10.079

Author’s references

[21] Y. Bansal, O. Silakari, The therapeutic journey of benzimidazoles: a review, Biorg. Med. Chem. 20 (2012) 6208-6236.

[22] H. Wang, Y. Wang, C. Peng, J. Zhang, Q. Zhu, Direct intramolecular C-H ami- nation reaction cocatalyzed by copper(II) and iron(III) as part of an efficient route for the synthesis of pyrido 1,2-a benzimidazoles from N-Aryl-2-aminopyridines, J. Am. Chem. Soc. 132 (2010) 13217-13219.

[23] J. Plutnar, M. Hromadova, N. Fanelli, S. Ramesova, Z. Havlas, L. Pospisil, Elec- tron transfer mechanism of substituted benzimidazoles: dimer switching, oscillations, and search for singlet fission properties, J. Phys. Chem. C 121 (2017) 9963-9969.

[24] S. Rajasekhar, B. Maiti, M.M. Balamurali, K. Chanda, Synthesis and medicinal applications of benzimidazoles: an overview, Curr. Org. Synth. 14 (2017) 40-60.

[25] X.-F. Han, M.-M. Chen, Z.-M. Zhou, Synthesis of several new 2-substituted benzimidazoles, J. Chem. Res. (2015) 407-409.

[26] P. Ghosh, R. Subba, MgCl2 center dot 6H(2)O catalyzed highly efficient synthesis of 2-substituted-1H-benzimidazoles, Tetrahedron Lett. 56 (2015) 2691-2694.

[27] V. Kumar, D.G. Khandare, A. Chatterjee, M. Banerjee, DBSA mediated chemoselective synthesis of 2-substituted benzimidazoles in aqueous media, Tetrahedron Lett. 54 (2013) 5505-5509.

[28] F.K. Behbahani, P. Ziaei, One-pot synthesis of 2-substituted benzimidazoles catalyzed by anhydrous FePO4, Chem. Heterocycl. Compd. 48 (2012) 1011-1017.

[29] H. Shi, B. Xu, H.-J. Zhu, Electrochemical and theoretical studies of 1-Alkyl-2-substituted benzimidazoles as corrosion inhibitors for carbon steel surface in HCl medium, Chin. J. Struct. Chem. 35 (2016) 1829-1839.

[30] J. Kovvuri, B. Nagaraju, A. Kamal, A.K. Srivastava, An efficient synthesis of 2-substituted benzimidazoles via photocatalytic condensation of o-phenyl-enediamines and aldehydes, ACS Comb. Sci. 18 (2016) 644-650.

[31] P.A. Frey, S.A. Whitt, J.B. Tobin, A low-barrier hydrogen-bond in the catalytic triad of serine proteases, Science 264 (1994) 1927-1930.

[32] W.W. Cleland, M.M. Kreevoy, Low-barrier hydrogen-bonds and enzymatic catalysis, Science 264 (1994) 1887-1890.

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