Methylene-hydantoin and Related Compounds. I. On the Reaction of Pyruvic Acid and Urea: The Synthesis of 5-Methylene-hydantoin

Abstract

Various condensation products were obtained by the reaction between pyruvic acid and urea. They are 5-hydroxy-5-methyl-hydantoin, homoallantoin, homoallantoic acid, and dipyruvic triureide. 5-Methylene-hydantoin was prepared from some of these compounds, or directly from pyruvic acid and urea, by reactions in organic acid. The most convenient method was the dehydration of 5-hydroxy-5-methyl-hydantoin, which is a new compound melting at 166°C. 5-Methylene-hydantoin, m. p. 214°C, is a new monomer of the vinylidene type which polymerizes easily by means of a free radical mechanism. 3-Methyl-5-methylene-hydantoin was also prepared from 5-hydroxy-5-methyl-hydantoin through its 3-methyl derivative.