Determination of the p/o-Isomer Product Ratios in Electrophilic Aromatic Nitration of Alkylbenzenes Using High Resolution ¹H NMR Spectroscopy

Michelle K. Waddell¹, Charles M. Bump¹, Edmund M. Ndip¹ and Godson C. Nwokogu^1,

¹Department of Chemistry and Biochemistry, Hampton University, Hampton, VA 23668, U.S.A.

Cite this paper

Michelle K. Waddell, Charles M. Bump, Edmund M. Ndip and Godson C. Nwokogu. Determination of the p/o-Isomer Product Ratios in Electrophilic Aromatic Nitration of Alkylbenzenes Using High Resolution ¹H NMR Spectroscopy. World Journal of Chemical Education. 2019; 7(3):216-224. doi: 10.12691/WJCE-7-3-5

Abstract

High resolution ¹H NMR spectroscopy, an increasingly available instrumental method, is used in undergraduate organic laboratory practice as a simpler alternative to gas chromatographic method for the direct determination of the p/o ratios of the crude reaction product from the nitration of alkylbenzenes. The choice of isopropylbenzene as a substrate illustrates that steric effect can be significant in controlling regioselectivity in electrophilic aromatic substitution reactions.

Keywords

laboratory instruction, organic chemistry laboratory, electrophilic aromatic substitution, nitration of aromatic compounds, regioselectivity, quantitative ¹H NMR spectroscopy

Copyright

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