Stereochemistry of 3-isopropoxy-3-methyl-1,3-oxasilinane-the first 3-silatetrahydropyran with an exo-cyclic RO-Si bond
- Molecular structure and conformational behavior of 3-isopropoxy-3-methyl-3-oxasilinane is studied by low temperature C-13 NMR spectroscopy and theoretical calculations (DFT, MP2). Two conformers, 1-ROax and 1-ROeq, were found experimentally and located on the potential energy surface. LT C-13 NMR spectroscopy gives almost equal population of the two conformers at 98 K with Delta G(98K)degrees=0.02 kcal/mol in favor of 1-ROax and Delta G(98K)(#)=4.5 kcal/mol. The corresponding DFT calculated values (Delta G(98K)degrees=0.03 kcal/mol, Delta G(98K)(#)=5.1 kcal/mol) are in excellent agreement with the experiment. Detailed DFT and MP2 calculations of the solvent effect on the conformational equilibrium were performed and highlighted the leveling out of the two conformers when transferred from gas to solution. (C) 2015 Published by Elsevier Ltd.
Verfasserangaben: | Bagrat A. Shainyan, Svetlana V. Kirpichenko, Erich KleinpeterORCiDGND |
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DOI: | https://doi.org/10.1016/j.tet.2015.07.047 |
ISSN: | 0040-4020 |
Titel des übergeordneten Werks (Englisch): | Tetrahedron |
Verlag: | Elsevier |
Verlagsort: | Oxford |
Publikationstyp: | Wissenschaftlicher Artikel |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2015 |
Erscheinungsjahr: | 2015 |
Datum der Freischaltung: | 27.03.2017 |
Freies Schlagwort / Tag: | 1,3-Oxasilinanes; Assignment of stereochemistry; Barrier to ring inversion; Conformational equilibrium; Solvent effects |
Band: | 71 |
Ausgabe: | 38 |
Seitenanzahl: | 7 |
Erste Seite: | 6720 |
Letzte Seite: | 6726 |
Fördernde Institution: | Russian Foundation for Basic Research [14-03-00923] |
Organisationseinheiten: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Chemie |
Peer Review: | Referiert |