Base-Catalysed Hydrolysis and Reactivity-Spectra Correlations of (Z)-4-Benzylidene-2-(Substituted Phenyl)Oxazol-5(4H)-ones

Abstract

Rate coefficients have been measured for the base-catalysed hydrolysis of a series of ( Z)-4-benzylidene-2-(substituted phenyl)-4 H-oxazol-5-ones in 70% v/v aqueous dioxan at various temperatures. The enthalpies and entropies of activation, and a Hammett reaction constant for the reaction, have been evaluated. The 1H and 13C NMR chemical shifts were assigned, as well as the IR carbonyl stretching frequencies in chloroform, after deconvolution and band separation. Successful correlations between the carbonyl stretching wavenumbers and the 13C NMR chemical shifts and the rates of the alkaline hydrolysis were found.