THE USE OF CYANIC ACID IN GLACIAL ACETIC ACID SOLUTION, AND IN MIXTURES OF GLACIAL ACETIC ACID WITH OTHER ORGANIC SOLVENTS. DERIVATIVES OF 1-ISOBUTYRIC ACID AMINO-5-DIMETHYLHYDANTOIN
Journal of the American Chemical Society
into cold water the hydantoin separated. It was purified by recrystallization from dilute alcohol and spearated in the form of balls of microscopic crystals. The compound melted from 180-185' and gave a positive test with Millon's reagent. It was dried for analysis a t I IO'. Calc. for ClzHlsObNa: N, 15.06. Found: N, 15.22, 15.20. 2-Thio-4-anisalhydantoin (XXVI) .-Johnson and O'Brienl first prepared this compound by condensing 2-thio-3-benzoylhydantoin with anisic aldehyde and finally
... d finally hydrolyzing the resulting benzoyl derivative with hydrochloric acid. The same compound was prepared for our work by condensing 2-thiohydantoin with anisic aldehyde in acetic acid solution and in the presence of sodium acetate. From 23 g. of the i-thiohydantoin we obtained 45 g: of the anisal compound. It was crystallized from glacial acetic acid and melted a t 260'. Calc. for CllH1002N2S: N, 1 1 .96. Found: N, 11.95. 2-Thio-4-anisylhydantoin (XXIX) .-The hydantoin was prepared by reduction of the above anisalhydantoin (XXVI) with sodium amalgam. The procedure was as follows: Five grams of the unsaturated hydantoin were suspended in a solution of 65 cc. of water and I O cc. of dilute sodium hydroxide and then 100 g. of 37f sodium amalgam added in small portions a t a time. After the amalgam had been added the solution was then filtered and acidified with hydrochloric acid, when the hydantoin separated in a crystalline condition. The yield of crude material was 4 . 5 g. In order to destroy any hydantoic acid present this material was suspended in hydrochloric acid and the mixture heated on the steam bath. The acid was finally completely evaporated and the hydantoin purified by crystallization from acetic acid. It separated from this solvent in plates and melted at 215'. The temperature was kept a t 75'.