ISSN:
0749-1581
Keywords:
Cobalt(III) porphyrins
;
Conformations
;
Azacyclooctane
;
Azacycloheptane
;
NMR
;
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A novel NMR shift reagent, cobalt(III) meso-tetraphenylporphyrin (CoTPP) was used to determine the conformations of azacycloheptane and azacyclooctane ligands complexed to the metalloporphyrin. Using the observed ring current shifts and a previously calibrated ring current model, the best agreement between the observed and calculated ring current shifts for azacycloheptane was obtained for a chair conformation, in agreement with previous theoretical and experimental studies on the conformational stability of seven-membered rings. The ring current shifts for azacyclooctane are best interpreted in terms of a mixture of many conformations. These results suggest that CoTPP may be useful as a probe of other conformationally mobile ligands.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mrc.1260280412
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