Abstract
Pechmann and Neger1) reported the reaction of acetonedicaboxylic acid with acetic anhydride to give dehydroacetocarboxylic acid (II), which transformed to its anilide (III) by the treatment with aniline. On the basis of chemical behavior and infrared data, we prefer the correct structures of these two being 3, 5-diacety 1-2H-pyran-2, 4, 6 (3H, 5H)- trione (V) and 1-phenyl-3, 5-diacety1-2, 4, 6-piperidinetrione (VI) respectively.
