title: Structural, conformational and vibrational properties of 1,1,1-Trifluoro-N-(1,1,2,2,2-pentafluoroethyl) methanesulfinimidoyl chloride, CF₃CF₂-N=S(Cl)CF₃.
abstract: The structural, conformational, and configurational properties of 1,1,1-Trifluoro-N-(1,1,2,2,2-pentafluoroethyl) methanesulfinimidoyl chloride, CF3CF2NS(Cl)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), 6-311+G(df) and 6-311+G(2df) basis sets]. According to these theoretical approximations, CF₃CF₂-N=S(Cl)CF₃ exists in the gas phase as a mixture of a favored anticlinal form (CN bond anticlinal with respect to the CSCl bisector) with C1 symmetry and a less abundant syn conformer showing C1 symmetry as well (ΔG° ≈ 1.20 kcal mol(-1)). Due to the small contribution only a few corresponding vibrational modes of the syn conformer could be assigned confidently in the experimental spectra. Compared to CF₃CF₂-N=S(F)CF₃, the replacement of F by Cl produces a clear change in NS bond length and the corresponding stretching frequency, without affecting the conformational properties.
authors.affiliation: INQUINOA - CONICET UNT, San Lorenzo 456, 4000 Tucumán, Argentina.
authors.forename: Norma L
authors.initials: NL
authors.lastname: Robles
authors.affiliation: Instituto de Química Física, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, San Lorenzo 456, 4000 Tucumán, Argentina.
authors.forename: Doly M
authors.initials: DM
authors.lastname: Chemes
authors.affiliation: Institut für Physikalische und Theoretische Chemie, Universität Tübingen, 72076 Tübingen, Germany.
authors.forename: Heinz
authors.initials: H
authors.lastname: Oberhammer
authors.affiliation: INQUINOA - CONICET UNT, San Lorenzo 456, 4000 Tucumán, Argentina. Electronic address: cutin@fbqf.unt.edu.ar.
authors.forename: Edgardo H
authors.initials: EH
authors.lastname: Cutin
mesh_terms: D005021:Ethylamines / Q000737:chemistry*; D007094:Imides / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D013455:Sulfur / Q000737:chemistry; D013457:Sulfur Compounds / Q000737:chemistry*; D013816:Thermodynamics; D014732:Vibration
chemical_list: D005021:Ethylamines; D007094:Imides; D013457:Sulfur Compounds; D013455:Sulfur
keywords: 1,1,1-Trifluoro-N-(1,1,2,2,2-pentafluoroethyl) methanesulfinimidoyl chloride; Conformational equilibrium; Quantum chemical calculations; Vibrational spectroscopy