Studies on the Proton Magnetic Resonance Spectra in Aromatic Systems. IX. Calculation of π-Electron Charge Density Distribution of the Substituted Benzene and Naphthalene Derivatives and ω-Technique

Abstract

ρNMR-π-electron charge density estimated from the revised shielding parameter-showed appreciable disagreement with that from HMO calculation using Streitwieser's parameter especially at meta position. The ω-technique has been applied to settle this problem and parameters for above treatment have been arranged so as to reconcile with ρNAR. Above treatments have also been applied to 1-substituted-3, 4-dimethoxybenzene, 2-substituted- and 2-substituted-6-methoxynaphthalene series, and favorable results have been acknowledged.