ISSN:
0749-1581
Keywords:
Benzonitriles
;
13C NMR
;
Substituent effects
;
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Carbon-13 NMR spectra are reported for 63 substituted benzonitriles in deuteriochloroform or in its mixture with dimethyl sulphoxide-d6. The substituent-induced chemical shifts (SCS) of the CN carbon correlate well with dual substituent parameters (DSP) in the para series but poorly in the meta series, whichever parameters are used. The DSP treatment was found to be inferior to principal component analysis (PCA), using as a probe 29 sets of literature data on α,β-unsaturated benzene derivatives. Whereas one component is sufficient for meta derivatives, two terms are needed for para derivatives, which are different for the α- and β-positions. The constants derived by PCA could be in principle used to predict further SCS, but their scope must be still explored.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mrc.1260270106
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