| Autor: |
M. E. Rennekamp, R. G. Cooks, J.V. Paukstelis |
| Rok vydání: |
1971 |
| Předmět: |
|
| Zdroj: |
Tetrahedron. 27:4407-4415 |
| ISSN: |
0040-4020 |
| DOI: |
10.1016/s0040-4020(01)98154-2 |
| Popis: |
Ring-chain tautomerism in 4,4-dimethyl-2-phenyloxazolidine and some aryl-substituted derivatives and keto-enol tautomerism in acetylacetone has been studied by a mass spectrometric method in which the concentration of each species involved in the tautomeric equilibrium is defined in terms of the abundance of a fragment ion uniquely associated with that species. From the effects of changes in source temperature at constant inlet temperature, and inlet temperature at constant source temperature, it is concluded that oxazolidine ring-chain tautomerism in the gas phase is an intramolecular process (which may involve wall collisions) while keto-enol tautomerism in acetylacetone is probably also unimolecular. Approximate values of enthalpy differences have been obtained and are comparable to those found in non-polar solutions. Changes in the spectra of aryl-substituted 2-phenyl-oxazolidines reflect the same trend towards more of the open form with electron-donating substituents as is observed in solution. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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