TRANSMISSION OF POLAR SUBSTITUENT EFFECTS IN 4`-SUBSTITUTED DIPHENYLACETYLENE-4-CARBOXYLIC ACIDS
A series of 4'-substituteddiphenylacetylene-4-carboxylic acids' alkaline hydrolysis rate coefficients were measured in 70%(v/v) dimethyl sulfoxide- water at 30.0 C. Using a solution of 80% (w/w) 2-methoxyethanol - water at 25.0 C, the pKa values of 4'- substituted diphenylacetylene-4-carboxylic acids have been determined. Esterification rate constants of corresponding acids with diazodiphenylmethane have been measured at 300C. For the transmission of dipolar ireversible dipolar substituent effects were seen for 4' - substituted diphenylacetylene-4-carboxylic acids. it was normal substituent effects are observed from 4`-substituted diphenylacetylene-4-carboxylic acids .Therefor it is conceivable to explain clearly the polar of substituent effect of the transmission via path of direct field of electrostatic in this system according to the results shown in tables 8,10 and 12.
Keywords: Polar Substituent,4`-Substituted Diphenylacetylene -4-Carboxylic Acids .