Synthesis of 3-imino and 3-ylideno derivatives of 4-fluoro-5-polyfluoroalkyl-1,2-dithiolenes

Reactions of 4-fluoro-5-polyfluoroalkyl-1,2-dithiol-3-thiones with hydroxylamine and hydrazines occur with replacement of the thiocarbonyl by imino group affording oximes and hydrazones respectively. N-Alkyl-and N-aryl-3-imino-1,2-dithiolenes formed in reactions of 3-chlorothio-1,2-dithiolium salts with primary alkyl-or arylamines. 3-Chlorothio-1,2-dithiolium salts react with compounds possessing an active methylene group yielding 3-ylideno derivatives of 1,2-dithiolenes.     

Synthesis of 4-Benzylsulfonyl-5-polyfluoroalkyl-ν-triazoles from 1,1-Dihydropolyfluoroalkyl Benzyl Sulfones

The reaction of 1,1-dihydropolyfluoroalkyl benzyl sulfones with sodium azide or trimethylsilyl azide in the presence of tertiary amines gives ammonium salts of 4-benzylsulfonyl-5-polyfluoroalkyl--triazoles. The proposed reaction scheme includes the participation of catalytic amounts of azide ion in the cyclization of the formed intermediate vinyl azides to triazoles. X-ray analysis of 1,4-diazabicyclo[2.2.2]octane salt of 4-benzylsulfonyl-5-(-H-hexafluoropropyl)--triazole has been carried out.     

An <Emphasis Type="Italic">ab initio</Emphasis> quantum-chemical study of the compounds HC≡CXCH<Subscript>3</Subscript> (X = O,S, Se)

The compounds HCCXMe (X = O, S, Se) were studied by the MP2(full)/6-31G* ab initio method using the method of natural bond orbitals. The parameters of the molecular geometry were obtained. The electron density distribution in these compounds is determined to a greater extent by the electronegativity of atoms X, than by conjugation of the lone electron pairs of the heteroatoms with the triple bond.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 11, 2004, pp. 1823–1827.Original Russian Text Copyright © 2004 by Bzhezovskii, Kapustin, Chura, Shermolovich.This revised version was published online in April 2005 with a corrected cover date.     

Synthesis of a new polyfluorinated vinylogue of tetrathiafulvalene through 1,3-dipolar cycloaddition of ethyl beta-bromoperfluorodithiocrotonate with dimethyl acetylenedicarboxylate

The ethyl ester of beta-bromoperfluorodithiocrotonic acid reacts with dimethyl acetylenedicarboxylate to give 1,4-difluoro-2,3-bis(trifluoromethyl)-but-2-ene-1,4-diylidene-2,2'-bis(4',5'-dicarbomethoxy-1',3'-dithiole) (4), a new type of vinylogue of tetrathiafulvalene. The thermal transformations of this compound lead, depending on the temperature, to the formation of the cyclization products: 11,14-difluoro-2,3,8,9-tetra(carbomethoxy)-12,13-bis(trifluoromethyl)-1,4,7,10-tetrathiadispiro[4.0.4.4]tetradeca-2,8,11,13-tetraene (8) or 5,8-difluoro-6,7-bis(trifluoromethyl)-2,3-bis(carboxymethyl)-1,4-benzodithiine (11).     

Sulfonimidamides and Imidosulfuric Diamides: Compounds from an Underexplored Part of Biologically Relevant Chemical Space

Two novel solid reagents—1-sulfonimidoyl- and 1-sulfamimidoyl-3-methylimidazolium derivatives—for the synthesis of sulfonimidamides and imidosulfuric diamides, respectively, were developed. It is shown that these reagents are very effective in substitution reactions with various N- and O-nucleophiles; therefore, they significantly extend the accessibility to the chemical space covered by organosulfur(VI) compounds with S=N bonds. In addition, previously unknown imidosulfuric diamides with free imino nitrogen groups were prepared, and their physical and chemical properties were characterized (including molecular geometry, pK_a, Log P, microsomal stability, and reactivity towards typical electrophiles). Similar to other organosulfur(VI) derivatives with S=N bonds, these compounds can be considered as promising bioisosteres of amides, ureas, or sulfonamides.     

Intermediate carbene formation in the reaction of thioamides with phosphorus (III) derivatives: Quantum chemical investigation

The reactions of perfluoroalkyl thioamides with trimethyl phosphine, trimethyl phosphite, and tris(dimethylamino)phosphine have been analyzed by means of quantum chemical (DFT and MP2) calculations. The reaction seems to proceed via the nucleophilic attack of the electrophilic carbon atom by the phosphorus lone pair with the formation of cyclic or acyclic adducts. The latter releases the thiophosphate molecule forming perfluoroalkylaminocarbene as the short‐lived intermediate. The reaction of the carbene with the second molecule of trialkyl phosphite yields phosphorus ylide. The ylide undergoes a migration of fluorine from carbon to phosphorus. The reactions of perfluoroalkyl thioamides with phosphines and tris(dimethylamino)phosphine probably proceeds differently. Using alkyl thioamides or amides instead of perfluoroalkyl thioamides also makes the reaction less favorable. The only combination of perfluoroalkyl thioamides with trialkyl phosphite fulfills both the kinetic requirements (moderate activation energies and relative energies for intermediates) and the thermodynamic aspects (higher stabilities of the reaction products compared with the starting materials). © 2013 Wiley Periodicals, Inc.     

Synthesis of 4-polyfluoroalkyl-1,3-dithiolanes via [3+2] cycloaddition of thiocarbonyl ylide to polyfluoroalkanethioamides

Chemistry of Heterocyclic Compounds - New 4-polyfluoroalkyl-1,3-dithiolanes were synthesized by reaction of polyfluoroalkanethioamides with thiocarbonyl ylide that was generated in situ by...     

Reactions of Alkyl 1H,1H-Perfluoroalkyl Sulfones with Ammonia, Amines, and Hydrazines

2,2,3,3-Tetrafluoropropyl and 2,2,3,3,4,4,5,5-octafluoropentyl alkyl sulfones react with ammonia, primary and secondary amines, hydrazine hydrate, phenylhydrazine, and N,N-dimethylhydrazine to afford, depending on the length of the polyfluoroalkyl chain and reaction conditions, the corresponding enamines, imines, or mono- and bis-hydrazones. The bis-hydrazone obtained from phenylhydrazine and 2,2,3,3,4,4,5,5-octafluoropentyl benzyl sulfone is capable of undergoing further dehydrofluorination to give 5-difluoromethyl- or 5-unsubstituted 1-phenylpyrazole.     

Molecular structure of 1-morpholino-3-phenyl-5,6,7,8-tetrachloro-1,2,4-benzothiadiazine

Institute of Organic Chemistry, Academy of Sciences of the Ukrainian SSR. Institute of Applied Physics, Academy of Sciences of the Moldavian SSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 32, No. 2, pp. 172–174, March–April, 1991.