Structural, conformational and vibrational properties of 1,1,1-Trifluoro-N-(1,1,2,2,2-pentafluoroethyl) methanesulfinimidoyl chloride, CF 3 CF 2 N S(Cl)CF 3
作者:Norma L. Robles、Doly M. Chemes、Heinz Oberhammer、Edgardo H. Cutin
DOI:10.1016/j.saa.2015.02.092
日期:2015.6
The structural, conformational, and configurational properties of 1,1,1-Trifluoro-N-(1,1,2,2,2-pentafluoroethyl) methanesulfinimidoyl chloride, CF3CF2-N=S(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(2d1) 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 (C-N bond anticlinal with respect to the C-S-Cl bisector) with C-1 symmetry and a less abundant syn conformer showing C-1 symmetry as well (Delta G degrees approximate to 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 N=S bond length and the corresponding stretching frequency, without affecting the conformational properties. (C) 2015 Elsevier B.V. All rights reserved.