A convenient oxidation method of 1-(2-chloroethyl)-4-formylpyrazoles followed by dehydrochlorination was developed for preparation of 1-vinyl-4-pyrazolecarboxylic acids. Dehydrochlorination rate was established to decrease with the growing number of electron-donor substituents.
A convenient oxidation method of 1-(2-chloroethyl)-4-formylpyrazoles followed by dehydrochlorination was developed for preparation of 1-vinyl-4-pyrazolecarboxylic acids. Dehydrochlorination rate was established to decrease with the growing number of electron-donor substituents.