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An IR study of thiocarboxylic acid N-(1-arenesulfonamido-2-phenyl-2,2-dichloroethyl- and -2,2,2-trichloroethyl)amides revealed intramolecular hydrogen bonds whose formation is accompanied by electron density delocalization and stabilization of conformations with quasiaromatic rings. Formation of chelate species was confirmed by AM1 calculations.  相似文献   
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A mechanism has been proposed for the reaction of 1,3-dichloropropene with ethane-1,2-dithiol in the system hydrazine hydrate–potassium hydroxide on the basis of DFT quantum chemical calculations [B3LYP/6-311++G(d,p)]. The proposed mechanism involves several consecutive steps, in particular nucleophilic substitution of chlorine at the sp3-hybridized carbon atom by sulfur, prototropic allylic rearrangement of the monosubstitution product with double bond migration toward the sulfur atom, dithiolane ring closure via nucleophilic attack of the second thiolate group on the carbon atom in the γ-position with respect to the second chlorine atom, and prototropic allylic rearrangement of 2-vinyl-1,3-dithiolane to more stable 2-ethylidene-1,3-dithiolane.  相似文献   
84.
2-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.  相似文献   
85.
N-(Polychloroethylidene)arene-and -trifluoromethanesulfonamides reacted with indole and N-substituted indoles to give the corresponding N-[2,2-dichloro(or 2,2,2-trichloro)-1-(1H-indol-3-yl)ethyl]-substituted sulfonamides. Unlike N-(2,2,2-trichloroethylidene)trifluoromethanesulfonamide, less electrophilic N-(poly-chloroethylidene)arenesulfonamides failed to react with 1-(4-nitrophenyl)-1H-indole. Previously unknown N,N’-bis(2,2-dichloroethylidene)biphenyl-4,4’-disulfonamide reacted with 1-benzyl-1H-indole at both azomethine fragments. Likewise, reactions of 1,6-bis(1H-indol-1-yl)hexane and 1,4-bis(1H-indol-1-ylmethyl)-benzene with N-sulfonyl trichloroacetaldehyde imines involved both indole rings in the former.  相似文献   
86.
The second-order polarization propagator approach (SOPPA) was used to calculate 13C-1H, 13C-13C, and 15N-1H coupling constants for a series of N-(polychloroethylidene)arenesulfonamides and N’-arylsulfonylformimidamides, and their configuration with respect to the C=N bond was determined by comparing the calculated data with the experimental values. All the examined compounds were found to exist in solution exclusively as the corresponding E isomers. The most favorable conformations and relative energies of the E and Z isomers in the gas phase were determined in terms of the second-order perturbation theory (MP2/6-311G**). N’-Arylsulfonylformimidamides are characterized by restricted internal rotation of the dialkylamino group about the C-N bond having an increased order. Original Russian Text ? K.A. Chernyshev, L.B. Krivdin, G.N. Rozentsveig, I.V. Ushakova, I.B. Rozentsveig, G.G. Levkovskaya, 2008, published in Zhurnal Organicheskoi Khimii, 2008, Vol. 44, No. 1, pp. 82–91. Dedicated to Full Member of the Russian Academy of Sciences G.A. Tolstikov on his 75th anniversary  相似文献   
87.
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.  相似文献   
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