Hydantoine, Thiohydantoine, Glykocyamidine, III. Über die Orientierung bei der Monobenzylierung des 5.5‐Diphenyl‐glykocyamidins

Abstract

(C~HS)~C---CO

The Chemistry Of The Glycocyamidines

“…Similarly, 2-ethylmercapto-4-benzal-2-imidazolin-5-one (LVIII) yields with an alcoholic solution of methylamine V2-methyl-5benzylideneglycocyamidine (LIX): However, the yield in the latter case is low (177). Analogous reactions take place between 2-methylmercapto-4,4-(or 5,5)-diphenyl-2-imidazolin-5(or 4)-one and various primary amines, e.g., 2-aminoethanol (59), benzylamine (197), and secondary amines (52,53), monoprimary monotertiary diamines (199), and hydrazine (311). The latter has also been subjected to the reaction with 1-methyl-2-methylmercapto-4,4-diphenyl-2-imidazolin-5-one (LX), the dimethyl derivative of 5,5-diphenyl-2-thiohydantoin (311), and the diamines mentioned above with the S-methyl derivatives of various other 2-thiohydantoins (200).…”

“…Thus, l-methyl-2-methylmercapto-4,4-diphenyl-2-imidazolin-5-one (LXIIIa) could not be brought to react with diethylamine in spite of applying much more energetic conditions than those needed for the smooth occurrence of the analogous reaction with 2-methylmercapto-4,4(or 5,5)-diphenyl-2-imidazolin-5(or 4)-one (LXIIIb) (53). Similarly, the S-alkylated thiohydantoins of the types LXIV and LXV could not be transformed into the corresponding glycocyamidines, or at best with very low yields, by heating them (C,H6)2C'^"CO with alcoholic ammonia (197,198). However, by performing the latter reactions in the presence of ammonium salts, e.g., ammonium chloride, iodide, or acetate, the transformations were achieved smoothly and under much less vigorous conditions (197,198).…”

“…Similarly, the S-alkylated thiohydantoins of the types LXIV and LXV could not be transformed into the corresponding glycocyamidines, or at best with very low yields, by heating them (C,H6)2C'^"CO with alcoholic ammonia (197,198). However, by performing the latter reactions in the presence of ammonium salts, e.g., ammonium chloride, iodide, or acetate, the transformations were achieved smoothly and under much less vigorous conditions (197,198). The catalytic activity of the ammonium salts on the ammonolysis of LXIV and LXV, which is a case of acid catalysis, may be considered as a parallel to the behavior of the same substances toward acids and bases; while being stable toward bases, they are transformed by acids even at room temperature slowly into the corresponding hydantoins.…”

“…As already mentioned, 2-thiohydantoins may be transformed also directly into glycocyamidines (103). This may be achieved by heating their alcoholic solutions in the presence of iodine and advantageously with pyridine (197) and ammonia or amines (62). However, the yields are not good.…”

“…V2-Acetyl-5-benzylidenecreatinine (CIV) may be methylated in the form of its potassium salt by methyl iodide to the 3-methyl derivative, which undergoes degradation by successive treatment with hydrochloric acid and potassium permanganate to V,V'-dimethylparabanic acid (168). 196a) and benzylated by benzyl chloride to the 3-benzyl derivative (197).…”