ORGN 130 |
| A total of eight peaks were observed earlier for the olefinic carbons of trans-cyclodecene at -154.9 degrees, corresponding to a total of five conformations, three of C1 symmetry and two of C2 symmetry. The range of relative free energies was only 0.6 kcal/mol, which made it impossible to assign conformations on the basis of energies and symmetries alone. Conformational assignments have been made by considering also the NMR chemical shifts obtained from ab initio calculations. An X-ray study of trans-5-cyclodec-1-yl p-nitrobenzoate will be described; the crystal showed disorder. The carbon NMR spectrum of the epoxide of trans-cyclodecene does not show decoalescence at low temperatures, and calculations predict that a C2 conformation resembling twist-boat-chair-chair cyclodecane is of lowest free energy |
|
Physical Organic Chemistry, Combinatorial and Process Chemistry, New Reactions and Methodology, Peptides, Proteins and Amino Acids
8:00 PM-10:00 PM, Sunday, April 6, 2008 Morial Convention Center -- Hall A, Poster
Division of Organic Chemistry |