Mechanism of the keto-enol tautomerism in radical cations and gas-phase closed-shell systems
The enol-keto tautomerism in radical cations has been considered to involve a symmetry-forbidden 1,3-hydrogen shift. An alternative process involves two consecutive 1,2-hydrogen shifts. The ..delta..H/sub f/'s of the intermediate ions formed by a 1,2-hydrogen shift in the radical cations of phenol and the enol form of acetic acid have been calculated to be 220 and 191 kcal/mol, respectively. These ..delta..H/sub f/'s indicate barriers to the keto-enol tautomerism via two consecutive 1,2-hydrogen shifts of 50 and 47 kcal/mol, respectively, in good agreement with previously determined experimental values of 55 and 51 +- 10 kcal/mol, respectively. The tautomerism in the closed-shell systems 1-butene reversible 2-butene, vinyl alcohol reversible acetaldehyde, H/sub 2/C==O/sup +/CH/sub 3/ reversible H/sub 3/CO/sup +/==CH/sub 2/, and CH/sub 3/CH==O/sup +/CH/sub 3/ reversible CH/sub 3/CH/sub 2/O/sup +/==CH/sub 2/ is discussed in terms of two consecutive 1,2-hydrogen shifts.
- Research Organization:
- Univ. of California, Berkeley
- OSTI ID:
- 5772956
- Journal Information:
- J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 101:24; ISSN JACSA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Stereochemistry and function of oxaloacetate keto-enol tautomerase
Pathways for the reaction of the butadiene radical cation, [C{sub 4}H{sub 6}]{sup {sm{underscore}bullet}+}, with ethylene
Related Subjects
400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
ACETALDEHYDE
ACETIC ACID
ALCOHOLS
ALDEHYDES
ALKENES
AROMATICS
BUTENES
CARBOXYLIC ACIDS
CATIONS
CHARGED PARTICLES
CHEMICAL REACTIONS
ENOLS
HYDROCARBONS
HYDROGEN TRANSFER
HYDROXY COMPOUNDS
IONS
ISOMERIZATION
KETO ACIDS
KINETICS
MONOCARBOXYLIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PHENOL
PHENOLS
RADICALS
REACTION KINETICS
SYMMETRY