Significance of Nucleophilic Solvation of Ammonium Bond (≡N⁺-H) in Protonated Amines: A Thought Provoking Physical-Organic Chemistry Lecture to Graduate Students

R. Sanjeev¹, V. Jagannadham^2, and R. Veda Vrath³

¹Department of Chemistry, Avanthi Degree and PG College, Hyderabad, India

²Department of Chemistry, Osmania University, Hyderabad, India

³Department of Chemistry, L N Gupta College, Hyderabad, India

Cite this paper

R. Sanjeev, V. Jagannadham and R. Veda Vrath. Significance of Nucleophilic Solvation of Ammonium Bond (≡N⁺-H) in Protonated Amines: A Thought Provoking Physical-Organic Chemistry Lecture to Graduate Students. World Journal of Chemical Education. 2013; 1(1):1-5. doi: 10.12691/WJCE-1-1-1

Abstract

Our mission has perceivedand still continuing exceptionalachievement on ‘Transforming chemistry research in to chemistry teaching’. In this course of events we have been able to publish several articles in the area of chemical education. In continuation of this,the present article using a total of 38 amines isone of our successful aftermaths of the importance of nucleophilic solvation of ammonium bond (≡N⁺-H in protonated amines.We have explained the significance of nucleophilicsolvation of ammonium bond in protonated aminesin a simple and lucid way using Taft linear polar free energy correlations of pK_a’sin aqueous solution and dipole moments in gas phase, in benzene, in cyclohexaneand of pure liquids of several primary, secondary and tertiary amines as a function of Taft polar substituent constants. Our performed Taft correlations showed that the solvation of ammonium bond in protonated aminesthrough ≡N⁺-H bond is worth understanding in terms of steric hindrance which is absent in gas phase, in benzeneand in cyclohexane as it imparts its substance in biology.

Keywords

nucleophilic solvation, ammonium bond, Taft correlations

Copyright

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