| Autor: |
K. Pihlaja, Alpo Nikkilä, Raimo Keskinen |
| Rok vydání: |
2010 |
| Předmět: |
|
| Zdroj: |
Bulletin des Sociétés Chimiques Belges. 85:435-439 |
| ISSN: |
0037-9646 |
| Popis: |
Chemical equilibration of epimeric 2-t-butyl-5-methyl-1, 3-oxathiolans led to -ΔHo=4.60±0.05 kJ mol−1 and -ΔSo=2.9±0.16 J mol−1K−1 for the trans cis equilibrium. From them and the values of 1H vicinal coupling constants the conformational energy of a ψ-axial 2-t-butyl group was estimated at 8.6±1.3 kJ mol−1. A microcalorimetric determination of the enthalpy difference for the epimer equilibrium resulted in a less accurate value of 4.5±1.0 kJ mol−1 and pointed out some disadvantages connected with the latter method. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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