| Autor: |
Roger Dommisse, Frank C. Alderweireldt, J. A. Lepoivre |
| Rok vydání: |
2010 |
| Předmět: |
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| Zdroj: |
Bulletin des Sociétés Chimiques Belges. 86:633-638 |
| ISSN: |
0037-9646 |
| Popis: |
The reaction kinetics of the redox system chloranil-1, 4-dihydropyridine (of the Hantzsch-ester type) is monitored by U. V.-spectroscopy. A possible reaction mechanism is discussed. Evidence for an ion-pair formation in a purely second-order reaction is given. Some catalytic effects are described. From the thermodynamic parameters it is clearly demonstrated that the electronic effects of the substituents are of an utmost importance. All reactions have large negative ΔS≠-values. The reduction of several functional groups with 1, 4-dihydropyridines have recently been intensively studied especially as test-case reactions for the coenzymes NADH and NADPH. Up to now only a limited amount of data on reaction velocities has been published (1). In the present paper the oxidation of several Hantzsch-esters (see table 1) is described with emphasis on reaction kinetics and structural effects. Chloranil is choosen as a suitable oxidans for practical purposes. A reaction mechanism is given for the well known reaction (fig. 1). |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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