Synthesis,Structure, and Chemical Transformations of 2-Chloroprop-2-en-1-yl Sulfones

A green approach was proposed for the synthesis of 2-chloroprop-2-en-1-yl sulfones in 47–94% yield. The molecular and crystal structures of 2-chloroprop-2-en-1-yl phenyl sulfone and 2-chloroprop-2-en-1-yl methyl sulfone were determined by X-ray analysis. π-Stacking interaction between the benzene ring and double bond was revealed in the crystal structure of 2-chloroprop-2-en-1-yl phenyl sulfone. Chloropropenyl sulfones were found to readily undergo dehydrochlorination to give stable allenyl sulfones and alkaline hydrolysis to produce the corresponding acetonyl sulfones. The latter can be converted to oximes by treatment with hydroxylamine hydrochloride.

     

Regioselectivity in the reactions of <Emphasis Type="Italic">N</Emphasis>-(polychloroethylidene)-sulfonamides with 1<Emphasis Type="Italic">H</Emphasis>-pyrrole and 1-methyl-1<Emphasis Type="Italic">H</Emphasis>-pyrrole

N-(2,2,2-Trichloroethylidene)arenesulfonamides react with 1H-pyrrole and 1-methyl-1H-pyrrole to give the corresponding N-[2,2,2-trichloro-1-(1H-pyrrol-2-yl)ethyl]arenesulfonamides. The reaction of N-(2,2,2-trichloroethylidene)trifluoromethanesulfonamide with pyrrole leads to a mixture of 2-mono-and 2,5-disubstituted pyrroles, whereas in the reaction with 1-methyl-1H-pyrrole only the 2-substituted compound is formed. N-(2,2-Dichloro-2-phenylethylidene)-4-methylbenzenesulfonamide reacts with 1H-pyrrole to form N-[2,2-dichloro-2-phenyl-1-(1H-pyrrol-2-yl)ethyl]-4-methylbenzenesulfonamide, and its reaction with 1-methyl-1H-pyrrole gives a mixture of 2-and 3-monosubstituted derivatives. The results of quantum-chemical calculations of the initial reactants and products indicate that the process is orbital-controlled. A good agreement is observed between the experimental data and theoretical conclusions concerning the dependence of the reaction regioselectivity on the nature of substituents in the electrophile molecule.     

C-amidoalkylation of pyrroles with <Emphasis Type="Italic">N</Emphasis>-trifluoromethylsulfonyl and <Emphasis Type="Italic">N</Emphasis>-arylsulfonyl polychloroaldehyde imines

N-(Trifluoromethylsulfonyl) and N-arylsulfonyl polychloroacetaldehyde imines reacted with pyrrole, 1-alkyl-, 1-benzyl-, and 1-(4-nitrophenyl)-substituted pyrroles, and bis-pyrroles to give the corresponding 2-[1-(sulfonylamino)polychloroethyl]-1H-pyrroles or mixtures of 2- and 3-[1-(sulfonylamino)polychloroethyl]-1H-pyrroles, depending on the nature of the Schiff base and substituent on the pyrrole nitrogen atom and reaction conditions. The first synthesis of 2,5-disubstituted NH-pyrrole by reaction of pyrrole with Schiff bases was described.     

Synthesis of new imidazo[2,1-<Emphasis Type="Italic">b</Emphasis>][1,3]thiazole derivatives from 2-amino-4-(2,2-dichlorovinyl)-1,3-thiazole and <Emphasis Type="Italic">N</Emphasis>-(2,2-dichloro-2-phenylethylidene)arenesulfonamides

2-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.     

Oxidation of N-(1-Hydroxypolychloroethyl)sulfonamides

N-(2,2,2-Trichloro-1-hydroxyethyl)- and N-(2,2-dichloro-1-hydroxy-2-phenylethyl)arenesulfonamides are oxidized with chromium(VI) oxide to give, respectively, N-(arylsulfonyl)trichloroacetamides and N-(arylsulfonyl)dichloro(phenyl)acetamides. Under analogous conditions N-(2,2,2-trichloro-1-hydroxyethyl)trifluoromethanesulfonamide is converted into 1,1,1-trichloro-2,2-bis(trifluoromethylsulfonylamino)ethane.     

3-Aminopropylsilatrane and Its Derivatives: A Variety of Applications

Silatranes arouse much research interest owing to their unique structure, unusual physical–chemical properties, and diverse biological activity. The application of some silatranes and their analogues has been discussed in several works. Meanwhile, a comprehensive review of the wide practical usage of silatranes is still absent in the literature. The ability of silatranes to mildly control hydrolysis allows them to form extremely stable and smooth siloxane monolayers almost on any surface. The high physiological activity of silatranes makes them prospective drug candidates. In the present review, based on the results of numerous previous studies, using the commercially available 3-aminopropylsilatrane and its hybrid derivatives, we have demonstrated the high potential of 1-organylsilatranes in various fields, including chemistry, biology, pharmaceuticals, medicine, agriculture, and industry. For example, these compounds can be employed as plant growth biostimulants, drugs, optical, catalytic, sorption, and special polymeric materials, as well as modern high-tech devices.     

Synthesis of Azaheterocyclic Cymantrene Derivatives

The reduction of acetylcymantrene with sodium tetrahydridoborate gave cymantrenylethanol which was acylated with 4,5-dichloroisothiazole- and 5-(4-methylphenyl)isoxazole-3-carbonyl chlorides to obtain esters containing a 1,2-thia(oxa)zole fragment. The condensation of acetylcymantrene with 5-arylisoxazole-3- carbaldehydes, (5-arylisoxazol-3-yl)methoxybenzaldehydes (Ar = Ph, 4-Tol), and 4,5-dichloroisothiazole-3- carbaldehyde afforded the corresponding (E)-3-(azol-3-yl)-1-cymantrenylprop-2-en-1-ones. The resulting α,β- unsaturated ketones reacted with semicarbazide hydrochloride and thiosemicarbazide to produce substituted 4,5-dihydro-1H-pyrazole-1-carboxamides and -1-carbothioamides, and their reaction with hydroxylamine hydrochloride led to the formation of 4,5-dihydroisoxazoles containing cymantrene and 1,2-azole fragments. Heterocyclization of azolylcymantrenylpropenones with guanidine gave 2-aminopyrimidine derivatives, and dihydropyrimidine-2-thiones were obtained by their reaction with thiourea.     

Reactions of Dichloroethenes with Sulfur in the System Hydrazine Hydrate–KОН

Vinylidene chloride and 1,2-dichloroethene react with sulfur in the system hydrazine hydrate–KОН with the formation of polyvinylenesulfide oligomer of molecular mass 1750–6120 Da containing also vinylenehydrazine and vinylenechloride links in the Z-configuration, and 1,4-dithiine in the yield up to 46%. In aqueous-hydrazine layer polysulfide anions S _n ^2– (n = 1–4), mainly S₂^2– were found. The mechanism of formation of oligomers and 1,4-dithiine is suggested, which includes in the first stage dehydrochlorination of dichloroethenes and generation of chloroacetylene.     

Reactions of Aroxy- and Arylsulfanylacetic Acids and Their Esters with N-(2,2,2-Trichloro-1-hydroxyethyl)sulfonamides and -carboxamides

C-Amidoalkylation of aroxy- and arylsulfanylacetic acids and their methyl esters was effected by reaction with N-(2,2,2-trichloro-1-hydroxyethyl)sulfonamides and -carboxamides in the presence of methane- or trifluoromethanesulfonic acids as catalyst and solvent. The process is regioselective, and the substitution occurs at the para-position with respect to the heteroelement-containing group.