Enol and Enethiol Occurrence for Some Ketones and Thioketones. Mass Spectrometry and Theoretical Calculations
Open Access
- 30 November 2004
- journal article
- research article
- Published by MDPI AG in International Journal of Molecular Sciences
- Vol. 5 (11) , 294-300
Abstract
The mass spectra of ketones can provide valuable information with regards to keto-enol equilibria occurring in the gas phase. Mass spectra of selected ketones and thioketones have been analysed and specific fragmentation assignments have been done to characterised and weigh co-existing keto and enol tautomers. Thioketones are of particular interest due to their tendency to shift the tautomeric equilibrium towards the enethiol form. The predictive value of this methodology is not only supported by the influence of these compound’s nature and size of the substituent on these equilibria but also by the good correlation found between the selected fragments abundances ratio and semi-empirical calculation (AM1) of the corresponding heats of tautomerization.Keywords
This publication has 17 references indexed in Scilit:
- Spectrometric and theoretical evidences for the occurrence of tautomeric structures of selected ketonesJournal of Molecular Structure: THEOCHEM, 2000
- Theoretical and matrix-isolation experimental study on 2(1H)-pyridinethione/2-pyridinethiolThe Journal of Physical Chemistry, 1990
- The relative ease of removing a proton, a hydrogen atom, or an electron from carboxamides versus thiocarboxamidesJournal of the American Chemical Society, 1988
- The first acid and ester enols: 2,2-bis(pentamethylphenyl)ethene-1,1-diol and 1-t-butoxy-2,2-bis(pentamethylphenyl)ethenol, and their oxidation to stable free radicalsJournal of the Chemical Society, Chemical Communications, 1987
- Quantum-Mechanical Prediction of Tautomeric Equilibria1986
- Sterically stabilized enols: a study employing the internal rotational barriers of the destabilized ketonesThe Journal of Organic Chemistry, 1976
- Die Elektronenaboorptionsspektren gesättigter aliphatischer ThioketoneSpectrochimica Acta, 1964
- Aliphatische ThioketoneAngewandte Chemie, 1964
- Prototropic Tautomerism of Heteroaromatic Compounds: II. Six-Membered Rings1963
- A Study of a Thioketo-Thioenol Tautomeric System. I. Ethyl Thiobenzoylacetate1Journal of the American Chemical Society, 1958