Successful application of the spin-delocalization substituent constants sigma(center dot) to the correlation of the UV spectra of some model compounds with para-Y-substituted phenyl groups

UV spectra of 16 p-Y-substituted phenylacetylenes (1-Ys), nine p-Y-substituted acetophenones (2-Ys) and six p-Y-substituted-p'-methylsulphonylstilbenes (3-Ys) were measured and correlated against spin-delocalization substituent constants (sigma(.)) with confidence levels above 99.9%. UV spectra of five ethyl 3-hydroxy-3-(p-Y-substituted-phenyl)-propanates (4-Ys) and five 1-(p-Y-substituted-phenyl)-3-butyn-1-ols (5-Ys) were also measured. Correlation analysis results are discussed. Some literature UV data were also successfully correlated by the dual-parameter equation.