Structural, conformational and vibrational properties of 1,1,1-Trifluoro- N-(1,1,2,2,2-pentafluoroethyl) methanesulfinimidoyl chloride, CF3CF2NS(Cl)CF3

NORMA L.ROBLES; DOLY M. CHEMES; HEINZ OBERHAMMER; EDGARDO H. CUTIN

SPECTROCHIMICA ACTA A: MOLECULAR AND BIOMOLECULAR SPECTROSCOPY

ELSEVIER

Lugar: Amsterdam; Año: 2015 vol. 145 p. 139 - 144

0584-8539

The structural, conformational, and configurational properties of 1,1,1-Trifluoro-N-(1,1,2,2,2-pentafluoroethyl)methanesulfinimidoyl chloride, CF3CF2ANS(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, CF3CF2ANS(Cl)CF3 exists in the gas phase as a mixture of a favored anticlinal form (CAN bond anticlinal with respect to the CASACl bisector) with C1 symmetry and a less abundant syn conformer showing C1 symmetry as well (DG 1.20 kcal mol1). 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 CF3CF2ANS(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.