1.
J Org Chem
; 64(13): 4580-4585, 1999 Jun 25.
Artigo
em Inglês
| MEDLINE
| ID: mdl-11674525
RESUMO
The (13)C spectrum of trans-cyclododecene (1) dissolved in propane showed seven peaks for the olefinic carbons at -164.5 degrees C, corresponding to three conformations of C(1) symmetry and a fourth conformation, with a population of 20.1%, of C(2) symmetry. The populations of the C(1) conformations were 57.0, 18.6, and 4.3%. Conformational space was searched for 1 using MM2. Free energies and populations were calculated by MM3, and the results of the low-temperature NMR study are discussed in terms of these calculations and the (13)C chemical shifts calculated for eight conformations by the GIAO method at the HF/6-311G level. The conformations of 1 and cyclododecane (2) are compared.