%0 Journal Article
%T Dual Substituent Parameter Modeling of Theoretical, NMR and IR Spectral Data of 5-Substituted Indole-2,3-diones
%A Ghazwan F. Fadhil
%A Hanan A. Radhy
%A Alexander Perj¨¦ssy
%A M¨¢ria £¿amal¨ªkov¨¢
%A Erkki Kolehmainen
%A Walter M.F. Fabian
%A Katri Laihia
%A Zora £¿ustekov¨¢
%J Molecules
%D 2002
%I MDPI AG
%R 10.3390/71100833
%X Correlations of AM1 and PM3 theoretical data, 13C-NMR substituent chemical shifts (13C-SCS) and IR carbonyl group wave numbers [¦Í(C3¨TO)] were studied using dual substituent parameter (DSP) models for 5-substituted indole-2,3-diones. For the C7 atom a reverse substituent effect attributed to extended ¦Ð-polarization was observed. On the other hand, the DSP approaches for the C3 atom showed normal substituent effects with some contribution of reverse effect supported strongly by 13C-SCS correlations. In the ¦Í(C3¨TO) and p(C3¨TO) DSP correlations the field effect contribution predominates over the resonance effect, which justifies the using of earlier suggested vibrational coupling (V-C) model for 5- and 6-substituted indole-2,3-diones.
%K 5-Substituted indole-2
%K 3-diones
%K AM1 and PM3 theoretical data
%K IR and NMR data DSP correlations
%K ¦Ð-polarization
%K reverse substituent effect
%U http://www.mdpi.com/1420-3049/7/11/833