The preparation and characterisation of a new interpseudohalogen, ClCS2N3,and (CS2N3)SS(CS2N3), a novel disulfurdipseudohalide

The formation of the new interpseudohalogen species, ClCS2N3 (1), was achie ved from reaction of the cyclic pseudohalogen (CS2N3)(2) with Cl-2. This re presents the novel synthesis of a chlorine compound containing the [CS2N3] pseudohalide moiety. Characterisation was achieved using IR and Raman spect roscopy with comparison to quantum chemical calculations at the B3LYP level of theory using a 6-311 + + G* basis set for all atoms, with the experimen tally observed vibrational spectra being in excellent agreement with the ca lculated vibrational data. The structure of this new interpseudohalogen was fully optimised and was found to constitute a planar, five-membered ring w ith an exocyclic chlorine-sulfur bond adopting C-s symmetry. In a further i nvestigation the reaction of [Na](+)[CS2N3}(-) with sulfur monochloride, (S 2Cl2) was carried out and the optimum structure for the resulting compound, (CS2N3)SS(CS2N3) (2) was investigated by means of quantum chemical calcula tions again at B3LYP level of theory using a 6-311 + + G* basis set for all atoms, with the compound being characterised by IR and Raman spectroscopy the vibrational spectra again being in very good agreement with that of the calculated vibrational spectra. The observation that the compound adopts a dimer structure with a disulfide bridge having C-1 symmetry is in agreemen t with the predicted structure optimised using quantum chemical calculation s. (C) 1999 Elsevier Science S.A. All rights reserved.