In reaction of excess thiols with alpha -aryisulfonyl-substituted enamides containing two chlorine atoms in P-position to the amide moiety the chlorine atoms and the arylsulfonyl group attached to the C=C bond are replaced by alkylthio or arylthio groups. The sulfur-containing enamides obtained undergo cyclization when treated with phosphorus pentachloride or thionyl chloride to furnish 4,5-dimercaptooxazoles used for preparation of the corresponding disulfonyl derivatives. The latter were also obtained by treating in succession the N-(1-arylsulfonyl-2,2-dichloroethenyl)carboxamides with sodium hydrosulfide, then with alkyl halides, and hydrogen peroxide in acetic acid.
In reaction of excess thiols with alpha -aryisulfonyl-substituted enamides containing two chlorine atoms in P-position to the amide moiety the chlorine atoms and the arylsulfonyl group attached to the C=C bond are replaced by alkylthio or arylthio groups. The sulfur-containing enamides obtained undergo cyclization when treated with phosphorus pentachloride or thionyl chloride to furnish 4,5-dimercaptooxazoles used for preparation of the corresponding disulfonyl derivatives. The latter were also obtained by treating in succession the N-(1-arylsulfonyl-2,2-dichloroethenyl)carboxamides with sodium hydrosulfide, then with alkyl halides, and hydrogen peroxide in acetic acid.