The action of arylamines on some substituted 2-Thiazolin-5-ones

Abstract

The heterocyclic ring in 2-aryl-4-arylmethylene- and 4-arylmethylene-2-benzylthio-2-thiazolin-5-ones is readily opened by the action of primary aromatic amines in acetic acid containing a catalyticamount of sodium acetate with the formation of 1,2-diaryl-4-arylmethylene-2-imidazolin-5-ones and of 3-aryl-5-arylmethylene-2-thiohydantoins respectively. 4-Benzylidene-1-(p-chloropheny1)-2-phenyl-2-imidazolin-5-one was also obtained by the cyclization of the anilide of α-(p-chlorothiobenzamido)-β-phenylacrylic acid under the same reaction conditions. A possible reaction mechanism is postulated.