Hans Bradaczek

Darstellung, Schwingungsspektren und Röntgenstrukturanalyse von Trifluor- und Trichloracetyltrischwefeltrinitrid, CX3CO-NS3N21 / Synthesis, Vibrational Spectra, and X-ray Structure Analysis of Trifluoro and Trichloroacetyl Trisulfurtrinitride, CX3CO—NS3N21

S4N4 reacts at 25 °C with trifluoro and trichloro acetic acid anhydride, respectively, to yield yellow crystalline CX3–CO–NS3N2 (X = F, Cl), the mass, infrared, and Raman spectra of which are reported. An X-ray structure analysis of monoclinic CF3CONS3N2 revealed a non-planar five-membered S3N2 ring containing an unusually long (2.206 A) sulfur-sulfur bond with one sulfur atom additionally connected to an exocyclic nitrogen atom by a multiple bond. Comparisons with the infrared spectra of S3N2O and ten compounds of type RNS3N2 allowed to identify four wavenumbers characteristic for the S3N2 ring. The relationship μ = 23.09d-27.27 has been derived for stretching vibrational wavelengths, μ (in μm), and bond distances, d (in Å), of sulfur-nitrogen bonds.