V. Yu. Serykh

Functionalization of highly electrophilic N-(2,2,2-trichloroethylidene)- and N-(2,2-dichloro-2-phenylethylidene) arenesulfonamides with dithiooxamide

Depending on the reactant ratio, dithiooxamide (ethanedithioamide) reacted as N-nucleophile or N,N′-binucleophile with highly electrophilic aldimines, N-(2,2,2-trichloroethylidene)- and N-(2,2-dichloro-2-phenylethylidene)arenesulfonamides, to give the corresponding mono- or bis-adducts, N-[2-polychloro-1-(arylsulfonylamino) ethyl]ethanedithioamides or N,N′-bis[2-polychloro-1-(arylsulfonylamino)ethyl]ethanedithioamides, in good yield.

Unexpected formation of benzofuran derivatives in the C-amidoalkylation of p-cresol with 4-chloro-N-(2,2-dichloro-2-phenylethylidene)benzenesulfonamide*

The C-amidoalkylation of p-cresol with 4-chloro-N-(2,2-dichloro-2-phenylethylidene)benzenesulfon-amide in the presence of H2SO4, oleum, or a mixture of H2SO4 and P4O10 was studied for the first time. It was shown that the reaction not only leads to the targeted 4-chloro-N-[2,2-dichloro-1-(2-hydroxy-5-methylphenyl)-2-phenylethyl]benzenesulfonamide but is also accompanied by unexpected formation of the heterocyclic derivatives 4-chloro-N-(5-methyl-2-phenyl-1-benzofuran-3-yl)benzenesulfonamide and 5-methyl-3-phenyl-2-benzofuran-2(3H)-one.

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

Abstract4-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.

New approach to the preparation of p-(1-cyanoethyl)arenesulfonamides by reaction of arylsulfonyl imines of polychloroacetaldehydes with acetone cyanohydrin

Reaction of N-(2,2,2-trichloroethylidene)- or N-(1-phenyl-2,2-dichloroethylidene)arenesulfonamides with acetone cyanohydrin in acetone in the presence of potassium carbonate led to the formation of N- (2,2,2-trichloro-1-cyanoethyl)- or N-(2-phenyl-2,2-dichloro-1-cyanoethyl)arenesulfonamides.

Synthesis of 2-(hydroxyethyl)mercapturic acid from p-acetylcysteine and 2-bromoethanol

In conditions of environmental pollution with organochlorine compounds the development of efficient methods for determining metabolites of ecotoxicants in the human body is a topical task. One of metabolites of electrophilic xenobiotics, in particular, of organochlorine pollutants, is 2-(acetylamino)-3-[(2-hydroxy-ethyl)sulfanyl]propionic [2-(hydroxyethyl)mercapturic] acid 1 that as known is formed in a human body as a result of metabolism of haloethanes or haloethylene [1, 2].

Reaction of polychloroacetaldehyde arylsulfonylimines with 2-amino-6H-1,3-thiazine-6-thiones and 2-amino-4-phenyl-6H-1,3-thiazin-6-one

Abstract2-Amino-4-R-6H-1,3-thiazine-6-thiones and 2-amino-4-phenyl-6H-1,3-thiazin-6-one react with highly electrophilic N-arylsulfonylimines of chloral and phenyldichloroacetic aldehyde at the exocyclic amino group affording in good yields products of nucleophilic addition to the azomethine group of imines: N-[2-polychloro-1-(6-thioxo-4-R-6H-1,3-thiazin-2-ylamino)ethyl]- or -[2-polychloro-1-(6-oxo-4-phenyl-6H-1,3-thiazin-2-ylamino)ethyl]arenesulfonamides.

Synthesis of new imidazo[2,1-b][1,3]thiazole derivatives from 2-amino-4-(2,2-dichlorovinyl)-1,3-thiazole and N-(2,2-dichloro-2-phenylethylidene)arenesulfonamides

Abstract2-Amino-4-(2,2-dichlorovinyl)-1,3-thiazole reacted with highly electrophilic N-(2,2-dichloro-2-phenylethylidene)- and N-(2,2,2-trichloroethylidene)arenesulfonamides through the exocyclic amino group to give products of nucleophilic addition to the azomethine bond, N-[2,2-di(or 2,2,2-tri)chloro-1-(1,3-thiazol-2-ylamino)ethyl]arenesulfonamides in good yields. Intramolecular heterocyclization of the latter afforded N-[3-(2,2-dichloroethyl)-6-phenylimidazo[2,1-b][1,3]thiazol-5-yl]arenesulfonamides.

Synthesis of 2-arylsulfonylamino-3-phenyl-3-chloropropanoic acids

The addition of N,N-dichloroamides to unsaturated compounds is a very effi cient method of preparation of versatile amino derivatives with a protected amino group [1–9]. Besides the adducts of dichloroamides with alkenes may be used further for functionalization using the supplemented synthetic opportunities provided by the introduction into the structure of a chlorine atom [10]. Among the most signifi cant functionalized alkenes used as substrates in reactions with dichloroamides the esters of unsaturated acids should be mentioned [1–4]. The known reactions of chloroamination of cynnamic acid esters open a prospect to the preparation of a wide range of synthetic amino acids, important biologically active substances or their direct synthetic precursors. The use of unsaturated acids instead of their esters in the reactions with chloroaminating agents would simplify the synthesis of amino acids in some cases by eliminating the stage of hydrolysis of the ester group. However the analysis of the published information showed that the unsaturated acids were not studied in these reactions. In order to develop the synthetic approach to the amino acids derivatives we studied in this research for the fi rst time the reaction of cinnamic acid with N,N-dichloroarenesulfonamides Iа–Ic synthesized by procedure [11]. Dichloroamides Iа–Ic react with cinnamic acid at boiling in CCl4 solution to form 2-arylsulfonylamino-3phenyl-3-chloropropanoic acids (β-chlorophenylalanine derivatives) IIа–IIc.

Synthesis of N-[1-(1H-Benzimidazol-2-ylsulfanyl)-2,2,2-trichloroethyl]arenesulfonamides by Reaction of N-(2,2,2-Trichloroethylidene)arenesulfonamides with 1H-benzimidazole-2-thiol

Electron-deficient character of the azomethine moiety in N-sulfonyl imines derived from polyhalocarbonyl compounds is determined by the effect of strong electron-withdrawing substituents, which favors their reactions with various nucleophiles and polynucleophiles [1]. Such transformations provide convenient approaches to various functionalized sulfonamide derivatives [1–14] as interesting models for stereochemical studies [5–8] and reagents [1, 9–16].

N,N-dichlorotriflamide in the reaction with cinnamic acid

B Cl H2O _HOCl TfNCl , I + + _ Reactions of N,N-dichloroarenes or sodium salts of arene sulfonic acids monochloroamides with esters of 3-arylpropenoic acids underlie a convenient and effi cient method of a targeted synthesis of versatile derivatives of synthetic amino acids [1–3]. Aiming at the development of a preparation methods for amino acids derivatives containing a trifl oromethylsulfonyl substituent we perform the studies of reactions between N,N-dichlorotrifl amide (I) with unsaturated acids and for the fi rst time we have investigated the reaction of dichloroamide I with cinnamic acid. In water without catalyst the reaction unexpectedly afforded N-(1-phenylethyl-2,2-dichloro)trifl amide (II) whose structure was unambiguously proved by 1D and 2D NMR spectroscopy and also by an independent synthesis [4]. It is presumable that the reaction involves a stage of the oxidative decarboxylation of the cinnamic acid to give β-chlorostyrene A. Further apparently an electrophilic addition of dichloroamide I to β-chlorostyrene occurs through a chloronium intermediate B with the formation of N-chloroadduct C followed by the reaction of the latter with water. The formation of β-bromostyrenes from 3-arylpropenoic acids at the treatment with N-bromosuccinimide was described in the literature [5, 6], and the electrophilic β-chloro-α-amidation of styrene derivatives effected by N,N-dichlorotoluenesulfonamide was also mentioned [7]. These processes proceeded exclusively in the presence of catalysts. But no information exists on similar noncatalytic processes.