Gas electron diffraction and quantum chemical study of the structure of a 2-nitrobenzenesulfonyl chloride molecule

A combined gas electron diffraction and quantum chemical (B3LYP/6-311+G**, B3LYP/cc-pVTZ, B3LYP/cc-pVTZ, midix (Cl), and MP2/cc-pVTZ) study of the structure of a 2-NO2-C6H4-SO2Cl molecule is performed. It is found experimentally that at a temperature of 345(5) K the gas phase contains two conformers of the C 1 symmetry. Conformer I with a nearly perpendicular arrangement of the S-Cl bond with respect to the benzene ring plane (the C(NO2)-C-S-Cl torsion angle is 84(3)°) is contained predominantly (69(12)%). In conformer II, the S-Cl bond is located near the benzene ring plane (the C(NO2)-C-S-Cl angle is 172(3)°). The following experimental internuclear distances (A) are obtained for conformer I: r h1(C-H) = 1.064(15), r h1(C-C)av = 1.397(3), r h1(C-S) = 1.761(6), r h1(S-O)av = 1.426(4), r h1(S-Cl) = 2.043(5), r h1(N-O)av = 1.222(4), r h1(C-N) = 1.485(16). In both conformers, the NO2 group is turned by more than 30° relative to the benzene ring plane.