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The keto–enol tautomerization of ethyl butylryl acetate studied by LC‐NMR
Author(s) -
Zhou Casey Chun,
Hill David R.
Publication year - 2007
Publication title -
magnetic resonance in chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.483
H-Index - 72
eISSN - 1097-458X
pISSN - 0749-1581
DOI - 10.1002/mrc.1930
Subject(s) - tautomer , chemistry , enol , keto–enol tautomerism , reaction rate constant , acetonitrile , solvent , kinetic isotope effect , proton nmr , solvent effects , organic chemistry , medicinal chemistry , computational chemistry , photochemistry , catalysis , kinetics , deuterium , physics , quantum mechanics
The keto–enol tautomerism of ethyl butylryl acetate was studied in mixed solvents under a variety of experimental conditions. The direct measurement of ketonization of the enol tautomer was performed by using the hyphenated technique LC‐NMR. The keto and enol tautomers can be separated by using HPLC and their interconversion is a slow process on the NMR timescale. The ketonization reaction was found to be acid catalyzed and the solvent isotope effect, k H 2 O / k D 2 O , in an acetonitrile/water mixture, is 5.4. The ketonization rate constants were also measured at different compositions of binary solvents, such as CH 3 CN/D 2 O, CD 3 OD/D 2 O, and CH 3 CN/CD 3 OD. The rate constant and water percentage were found to have an exponential relationship. The reaction rate as a function of solvent polarity will be discussed in this paper. Copyright © 2006 John Wiley & Sons, Ltd.