The supramolecular structure of the crystal products--[2-chloro-2-(silatranyl)ethyl]-4-nitro-benzenesulfonamide and -chloro--[2-chloro-1-(silatran-1-yl-methyl)ethyl]benzene-sulfonamide was established by X-ray diffraction analysis data, FTIR spectroscopy and DFT quantum chemical calculations. Their crystal lattice is formed by cyclic dimers with intermolecular hydrogen NH∙∙∙O-Si bonds and CH∙∙∙O=S short contacts. The distribution of electron density in the monomers was determined using quantum chemical calculations of their molecular electrostatic potential (MESP) in an isolated state (in gas) and in a polar medium.
View Article and Find Full Text PDFThe aza-Michael reaction of 3-aminopropyltriethoxysilane () and -silatrane () with acrylates affords functionalized silyl-(-) and silatranyl-(-) mono- and diadducts with up to a 99% yield. Their structure has been proved with IR and NMR spectroscopies, mass spectrometry and XRD analysis. The hydrolytic homo-condensation of triethoxysilanes - gives siloxanes -, which form complexes with Ag, Cu, and Ni salts.
View Article and Find Full Text PDFThe article is devoted to heterocyclization of bis(2-chloroprop-2-en-1-yl)sulfide which proceeds in hydrazine hydrate-alkali medium and leads to formation of thiophene and pyrrole derivatives: previously described 4,5,9,10-tetrahydrocycloocta[1,2-c;5,8-c']dithiophene, as well as unknown hydrazone of 5-methylidene-3-methyldihydrothiophen-2-one and 1-amino-2-(propynylsulfanylpropenylsulfanyl)-3,5-dimethylpyrrole. Tentative mechanisms for the formation of the heterocyclic products are discussed. Obtained hydrazone of 5-methylidene-3-methyldihydrothiophen-2-one was used for the synthesis of a range of azine derivatives and in oxidation process with SeO.
View Article and Find Full Text PDFSilatranes 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.
View Article and Find Full Text PDFα-Functionalized α,β-unsaturated aldehydes is an important class of compounds, which are widely used in fine organic synthesis, biology, medicine and pharmacology, chemical industry, and agriculture. Some of the 2-substituted 2-alkenals are found to be the key metabolites in plant and animal cells. Therefore, the development of efficient methods for their synthesis attracts the attention of organic chemists.
View Article and Find Full Text PDFN-(1-Aryl-2-polychloroethyl)arenesulfonamides obtained on the basis of N,N-dichlorosulfoamides and polychloroethenes or phenylacetylene undergo a reaction cascade in the presence of mercaptoethanol. The reaction cascade opens a new route to the series of cyclic or open-chain sulfonamide derivatives. The process includes cyclization to aziridine intermediates, their further recyclization, and isomerization to imidoylchlorides or chloroimines, followed by substitution or reduction under the action of mercaptoethanol or hydrolysis.
View Article and Find Full Text PDFCarbon-carbon coupling constants have been experimentally measured using the INADEQUATE pulse sequence in the series of N-[1,2-bis(dialkylamino)-2-arylethylidene]arylsulfonamides obtained from N-(1-aryl-2,2,2-trichloroethyl)amides of arylsulfonic acids. Comparison of the experimental J(C,C) in this series with those calculated at the SOPPA (Second-Order Polarization Propagator Approach) level in the model aminosulfonylamidine provided an unambiguous assignment at the C=N bond of the eight-title aminosulfonylamidines to E-configuration, while the unknown J(C,C) couplings in their inaccessible diverse Z isomers have been predicted with high reliability. The established marked difference between J(C,C) of the corresponding carbon-carbon bonds in cis and trans orientations to the nitrogen lone pair in aminosulfonylamidines provides a powerful tool in the configurational assignment at the C=N bond in a wide series of the related systems containing the C=N-SO2R moiety.
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