## Abstract ^13^C NMR spectra of a large number of polyalkylated benzenes with branched and linear aliphatic chains have been studied. This resulted in the development of a general procedure that can be used for the calculation of the aromatic chemical shifts in any polyalkylated benzene.
13C NMR Studies: Effect of steric compression on chemical shifts of carbons in diastereoisomers
β Scribed by Mahavir Prashad; M. Seth; A. P. Bhaduri; Avijit Banerji
- Publisher
- John Wiley and Sons
- Year
- 1980
- Tongue
- English
- Weight
- 148 KB
- Volume
- 14
- Category
- Article
- ISSN
- 0749-1581
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β¦ Synopsis
Abstract
^13^C NMR of diastereoisomeric pairs of 2,3βdiarylβ2βmethylbutyronitriles revealed a difference in the chemical shift of the carbon atoms between the diastereoisomers and the observed shifts were greatly influenced by the presence of an ortho substituent in the 3βphenyl ring.
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Exchange of amide protons with deuterium results in changes of 13 C chemical shifts for carbon atoms near the site of substitution (CH{N and N{C|O). There is a measurable decrease in the isotopic shifts of CH{N for cycloalkylacetamides as ring size increases from 3 to 8 and for lactams as ring size
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