Grilli, Stefano ; Lunazzi, Lodovico ; Mazzanti, Andrea ; Pinamonti, Marco ; Anderson, J. Edgar ; Ramana, C. V. ; Koranne, Priti S. ; Gurjar, Mukund K. (2002) Conformational studies by dynamic NMR. 91.1 Conformational stereodynamics of tetraethylmethane and analogous C(CH2X)4 compounds Journal of Organic Chemistry, 67 (18). pp. 6387-6394. ISSN 0022-3263
Full text not available from this repository.
Official URL: http://pubs.acs.org/doi/abs/10.1021/jo025984k
Related URL: http://dx.doi.org/10.1021/jo025984k
Abstract
Variable-temperature NMR studies of tetraethylmethane (1a), tetrapropylmethane (1b), tetrachloromethylmethane (1c), tetrabromomethylmethane (1d), tetracyclopropylmethylmethane (1e), and tetrabenzylmethane (1f) show a range of dynamic behavior. Separate signals for two types of conformation are observed for 1a, 1c, and 1d at low temperatures, with more than 95% of the molecules in a time-averaged D2d conformation, and the S4 conformation as the minor populated alternative. Compound 1e populates only S4-type conformations but equilibrates slowly between degenerate versions of these at low temperatures. Compounds 1b and 1f show a temperature-dependent spectrum but the low-temperature limit spectrum could not be observed. Ab initio calculations agree well with experiment on the conformational equilibria and suggest in particular that compounds 1b and 1f behave similarly to compounds 1a and 1e, respectively. A crystal structure of compound 1f is reported.
Item Type: | Article |
---|---|
Source: | Copyright of this article belongs to American Chemical Society. |
ID Code: | 11363 |
Deposited On: | 09 Nov 2010 05:07 |
Last Modified: | 02 Jun 2011 09:52 |
Repository Staff Only: item control page