ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
(-)-β-Caryophyllene (1) adopts three conformations in solution: αα(48%), βα(28%), and ββ(24%). The conformations were identified by an analysis of the 13C- and 1H-NMR spectra at -87.2 and -153.8° in connection with APT, HETCOR, and COSY spectra, and subsequent NOESY experiments. The activation parameters of the conversion αα → βα were determined from a bandshape analysis of exchange-broadened 13C-NMR spectra of 8-[methylene-13C]-1 to give ΔH≠ = 5.9 ± 0.3 kcal/mol, ΔS= = -8.1 ± 1.8 cal/mol. · K. and ΔG298≠ = -8.3 ± 0.8 kcal/mol. The observed population ratio of the different conformers is best described by MM3.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19970800615
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