CH3N=SF2=NCH3: Structural, Conformational, and Configurational Properties in the Gaseous and in the Condensed Phases

CH3N=SF2=NCH3 (1) was obtained in 88% yield from the reaction of a bis(silylated) amine RN(SiMe3)2 with a sulfur tetrafluoride imide RN=SF4 (R = R = CH3). Single crystals suitable for X-ray crystallography were obtained by low-temperature crystallization; the data were collected at 120 K. Compound 1 crystallizes in the monoclinic space group P21/c with a = 5.8356(7) Å, b = 12.1665(14) Å, c = 8.1488(8) Å, Beta = 110.381(7)°, Z = 4, in the anti-anti form (whereby anti or syn describe the orientation of the N-CH3 bonds with respect to opposite S=N bonds). The structural, conformational, and configurational properties of CH3N=SF2=NCH3 were studied by vibrational spectroscopy [IR (gas) and Raman (liquid)] and quantum chemical calculations [B3LYP and MP2 with 6-311+G(2df,p) and cc-pVTZ basis sets]. Vibrational spectroscopy in the gas and liquid phases shows evidence of a configurational equilibrium of the anti-anti form and a slightly less favored anti-syn form of CH3N=SF2=NCH3.Fil: Robles, Norma Lis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; Argentina. Universidad Nacional de Tucumán; ArgentinaFil: Parsons, Simon . University of Edinburgh; Reino UnidoFil: Mews, Rüdiger . Universitat Bremen; AlemaniaFil: Oberhammer, Heinz . Universität Tübingen; Alemani

(Perfluoralkyl)(dimethylamino)sulfonium-hexafluoroarsenate

MeN = S(CF3)2 (5) is alkylated by Me3O AsF6 to Me2N-S(CF3)2 AsF6 (4). From 5 and MeOp. AsF6 (6) MeOS(O)-N(Me)S(CF3)2 AsF6 (7) is formed as a relatively stable primary product. Decomposition of 7 gives the expected 4 only in poor yield. Nucleophilic substitution of the sulfur-bonded fluorine in CF3SF2 AsF6 (8) by Me3SiNMe2 yields CF3S(NMe2)2 AsF6 (9). Similarly, (CF3)2CFSF2 AsF6 (10) reacts with dimethyl(trimethylsilyl)amine to give (CF3)2CFS(NMe2)2 AsF6 (11). The structures of 4 and 9 are elucidated by X-ray analyses, and the influence of the substituents on the bonding is discussed

CF3CF2N=S(F)CF3: Vibrational spectra and conformational properties

The structural, conformational, and configurational properties of 1,1,1-trifluoro-N-(1,1,2,2,2-pentafluoroethyl) methanesulfinimidoyl fluoride, CF3CF2N=S(F)CF3 have been studied by vibrational spectroscopy [IR (vapor) and Raman (liquid)] and quantum chemical calculations [B3LYP, MP2 and B3PW91 levels of theory (using the 6-311+G(d) and 6-311+G(2df) basis sets). According to these theoretical approximations,CF3CF2N=S(F)CF3 might be found in the gas phase as a mixture of a favoured anticlinal form (CAN bond anticlinal with respect to the CASAF bisector angle) and a less abundant syn conformer showing C1 symmetry as well (DG 1.5 kcal mol1). However, corresponding vibrational modes for these conformers show only small shifts which would not allow confidently detecting the rather small contribution of this second form in the experimental spectra.Fil: Robles, Norma Lis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; Argentina. Universidad Nacional de Tucumán; ArgentinaFil: Oberhammer, Heinz . Universität Tübingen; AlemaniaFil: Mews, Rüdiger . Universitat Bremen; AlemaniaFil: Cutin, Edgardo Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; Argentina. Universidad Nacional de Tucumán; Argentin

Isocyanatosulfonium Salts

RR'SF2 reacts with Me3SiNCO to give the corresponding N-(fluoroformyl)sulfur imides FC(O)NSRR' [R = NMe2, R' = F (7); R' = CF3 (9)]. From these AsF5 abstracts F- with formation of isocyanatosulfonium salts ONC - SRR' + AsF-6 [R = F, R' = CF3 (6); R = NMe2, R' = F (8); R = NMe2, R' = CF3 (10)]. The spectroscopic properties of the fluoroformyl derivatives and of the isocyanato salts are discussed. The structures of 8 and 10 are determined by X-ray analyses

Structure and Conformational Properties of N-Pentafluorosulfur(sulfuroxide difluoride imide) SF 5 NS(O)F 2 : Vibrational Analysis, Gas Electron Diffraction, and Quantum Chemical Calculations

The molecular structure and conformational properties of  N- pentafluorosulfur(sulfuroxide difluoride imide), SF5N=S(O)F2, have been studied by vibrational spectra (IR(gas) and Raman(liquid)), by gas electron diffraction (GED) and by quantum chemical calculations (MP2 and B3LYP with (6-31G(d) and 6-311+G(2df) basis sets). According to GED the prevailing conformer possesses a syn structure (N-SF5 bond synperiplanar with respect to the bisector of the SF2 group).  Splitting of the symmetric N=S=O stretching vibration in gas and liquid spectra demonstrates the presence of a second conformer (11(5)%) with anticlinal orientation of the N-SF5 bond according to quantum chemical calculations. The geometric structure, conformational properties and vibrational frequencies are well reproduced by quantum chemical calculations.Fil: Alvarez, Rosa Maria Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Cutin, Edgardo Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Mews, Rüdiger. Universitat Bremen; AlemaniaFil: Oberhammer, Heinz. Universität Tübingen; Alemani