Preparation and Properties of Chlorosulfuryl Chloroformate, ClC(O)OSO₂Cl

Abstract

The novel chlorosulfuryl chloroformate, ClC-(O)OSO 2 Cl, was prepared by the reaction of CCl 4 and SO 3 . Alternatively, the compound was obtained from the direct insertion reaction of SO 3 to Cl 2 CO. The latter reaction constitutes also a confirmation of the proposed mechanism for the former one. Density functional theory and MP2 theoretical approximations predict the existence of two conformers, syn−gauche and syn−anti, depending on the value adopted by the dihedral angles ϕ(Cl−C−O−S) and ϕ(C−O−S−Cl). The structure of the syn−gauche conformer was determined by gas-phase electron diffraction (GED). The existence of the syn−anti conformer can be neither confirmed nor excluded by the GED experiment. Vibrational spectra (vapor-phase and argon-matrix Fourier transform infrared and liquid Fourier transform Raman) were interpreted by an equilibrium mixture between both conformers.

Conformational Analysis of Trifluoroacetyl Triflate, CF₃C(O)OSO₂CF₃: Experimental Vibrational and DFT Investigation

“…6 and 8 and references cited therein). In this sense, a close and wellknown example is the ClC(O)OSO2Cl molecule, where the gauche conformation predominates over the anti [9].…”

Conformational Analysis of Trifluoroacetyl Triflate, CF3C(O)OSO2CF3: Experimental Vibrational and DFT Investigation

“…[6,8] and references cited therein). In this sense, a close and well-known example is the ClC(O)OSO 2 Cl molecule, where the gauche conformation predominates over the anti [9].…”