Cascade synthesis of 2-amino-5-(4-methoxyphenyl)-4-phenyl-1,3-thiazole by reaction of 4-chloro-N-[2,2-dichloro-1-(4-methoxyphenyl)-2-phenylethyl]benzenesulfonamide with thiourea
摘要:
4-Chloro-N-[2,2-dichloro-1-(4-methoxyphenyl)-2-phenylethyl]benzenesulfonamide reacted with thiourea on heating in DMF in the presence of sodium carbonate to give 5-(4-methoxyphenyl)-4-phenyl-1,3-thiazole-2-amine. A probable reaction scheme includes cyclization of the initial N-dichloroethyl amide to N-sulfonyl-2,3-diaryl-2-chloroaziridine which undergoes isomerization with opening of the three-membered ring to 1-arylsulfonylamino-2-chloro-2-(4-methoxyphenyl)-1-phenylethene. The subsequent heterocyclization in the reaction with thiourea is accompanied by aromatization via elimination of the arenesulfonamide fragment.
Benzene, toluene, and 2-chlorothiophene regioselectively react with N-(2,2-dichloro-2-phenylethylidene)arenesulfonamides in the presence of oleum to give N-[1-aryl(or hetaryl)-2,2-dichloro-2-phenylethyl]arenesulfonamides. Analogous C-amidoalkylation products are formed by the action of N-(2,2-dichloro-1-hydroxy-2-phenylethyl)- and N-(1-arylsulfonylamino-2,2-dichloro-2-phenylethyl)arenesulfonamides on toluene and 2-chlorothiophene in concentrated sulfuric acid.
Amidine derivatives of α-arylglycines from N-(1-aryl-2,2,2-trichloroethyl)amides of arenesulfonic acids and secondary amines
作者:Igor B. Rozentsveig、Galina G. Levkovskaya、Gulnur N. Rozentsveig、Anna N. Mirskova、Leonid B. Krivdin、Ludmila I. Larina、Aleksandr I. Albanov
DOI:10.1016/j.tetlet.2005.10.079
日期:2005.12
The interaction of N-(1-aryl-2,2,2-trichloroethyl)amides of arenesulfonic acids with secondary amines or their salts in the presence of inorganic bases involves the formation of chloroaziridine intermediates. Depending upon the solvent and reagent ratio, the reaction results in N-[1-dialkylamino-2-chloro-2-arylethylidene]-, N-[2-dialkylamino-1-chloro-2-arylethylidene]-, N-[1,2-bis(dialkylamino)-2-arylethylidene]-