Process for preparing 5-(4-hydroxyphenyl)hydantoin
AssigneeKanegafuchi Kagaku Kogyo Kabushiki Kaisha
InventorsKoji Yoneda, Takehisa Ohashi, Tomoaki Nagamachi, Hirotaka Fukumitsu, Satomi Takahashi
Life of this patent
Estimating the term…
Abstract
A process for preparing 5-(4-hydroxyphenyl)hydantoin by reacting glyoxylic acid, urea and phenol in an aqueous medium in the presence of an acid at an elevated temperature. The hydantoin of high purity can be readily prepared in good yields.
Claims5
A process for preparing 5-(4-hydroxyphenyl)hydantoin which comprises subjecting glyoxylic acid, urea and phenol to reaction in an aqueous medium at a temperature of not less than 40.degree. C. in the presence of a strong mineral acid, the concentration of which in the reaction system is not less than 2 N.
Dependencies are inferred from the claim text.