## Abstract An additivity relationship of substituent effects on the formyl proton chemical shift has been tested with ten disubstituted benzaldehydes. In most cases it is found that the formyl proton chemical shift, extrapolated to infinite dilution in nitromethane, is in good agreement with that
Substituent effects on the charge density in the formyl group
β Scribed by M. Eisenstein; F. L. Hirshfeld
- Publisher
- John Wiley and Sons
- Year
- 1983
- Tongue
- English
- Weight
- 695 KB
- Volume
- 4
- Category
- Article
- ISSN
- 0192-8651
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β¦ Synopsis
SCE' wavefunctions with similar extended Gaussian bases for the series HCOX with X = H, OH ( s y n and a n t i ) , NHz, CN, and F yield closely similar charge deformation density maps in the formyl region of all six molecules. The differences, measured by moments of partitioned atomic deformation densities, correlate almost linearly with the Hammett substituent parameters GI and CTR of the several substituents X. However, systematic deviations, especially in the carbon fragment, suggest the need for modified values of the inductive parameters GI for the correlation of these molecular charge densities.
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