World Journal of Chemical Education
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World Journal of Chemical Education. 2019, 7(3), 216-224
DOI: 10.12691/wjce-7-3-5
Open AccessArticle

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. Nwokogu1,

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

Pub. Date: August 25, 2019

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

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