STUDIES ON STOBBE CONDENSATION: REACTIONS OF ALDEHYDES AND KETONES WITH DIMETHYL METHYLSUCCINATE

Abstract

Benzaldehyde, o-methoxybenzaldehyde, p-chlorobenzaldehyde, benzophenone, and acetophenone are condensed with dimethyl methylsuccinate in the presence of potassium tert-butoxide to give the corresponding β-half-esters. In the case of o-methoxybenzaldehyde the lactonic acid (IX) is also obtained. The β-half-esters are cyclized by sodium acetate and acetic anhydride to the corresponding acetoxynaphthoates which are converted into their methoxynaphthoates. Alkaline hydrolysis of the β-half-esters yields the corresponding itaconic acids, the anhydrides of which are converted to their α-half-esters.