ISSN:
0009-2940
Keywords:
[3.3]Paracyclophane / Conformational analysis / Dynamic NMR spectroscopy / Tri-n-butyltin deuteride
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
According to a VT-NMR study, [2,2,11,11-D4][3.3]paracyclophane (1-D4) exists as a mixture of chair and boat conformers in the ratio of 1.0: 1.3 (ΔGo = 0.1 kcal/mol) at -70°C with an energy barrier for the chair-boat inversion of 12.0 kcal/mol (270 MHz, ca. 1% CD2Cl2 solution, Tc = - 15°C). The conformer ratio (chair/boat) is dependent on the concentration of 1-D4; it is 1:1 in ca. 1% CD2Cl2 solution but 1:2 in ca. 5% CD2Cl2 solution, due to preferential crystallization of the chair conformer.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19901230334
Permalink
