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Principal component analysis of the 13C NMR shifts of norbornyl derivatives

✍ Scribed by J. G. Ribeiro Tostes; P. R. Seidl; R. E. Bruns

Publisher: John Wiley and Sons
Year: 1989
Tongue: English
Weight: 785 KB
Volume: 27
Category: Article
ISSN: 0749-1581
DOI: 10.1002/mrc.1260270314

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✦ Synopsis

Principal component analysis was applied to the 13C NMR chemical shifts of the seven carbon atoms of the norbornyl framework for 75 molecules. Two two-dimensional principal component projections are shown to be sufficient to distinguish the main electronic and steric substituent effects contributing to these shifts. These effects allow a comparison of the (three-, four-and five-membered) ring and non-ring substituents and their influence on the shifts of carbon atoms of the norbornyl framework. Four classes of molecules, each with characteristic chemical behaviour, are identified. Exo-endo class discrimination and exo-endo patterns of isomer pairs are emphasized, especially with regard to cyclic substituents on norbornyl systems.

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