Intramolecular electrophilic cyclization of functional derivatives of unsaturated compounds: III. Reaction of N,4-Diarylbut-3-enamides with arenesulfenyl chlorides. Synthesis of 5-aryl-4-arylsulfanyl-2,3,4,5-tetrahydro-1H-1-benzazepin-2-ones

Abstract

N-Aryl-4-phenylbut-3-enamides reacted with arenesulfenyl chlorides in chloroform to give N,4-diaryl-3-arylsulfanyl-4-chlorobutanamides, whereas in acetic acid in the presence of lithium perchlorate N-[4-arylsulfanyl-5-phenyltetrahydrofuran-2-ylidene]arenaminium perchlorates were obtained. Reactions of arenesulfenyl chlorides with N,4-diarylbut-3-enamides having strong electron-donating groups in positions 3 and 4 of the N-aryl substituent afforded 5-aryl-4-arylsulfanyl-2,3,4,5-tetrahydro-1H-1-benzazepin-2-ones.