Roberto Maggiulli

Synthesis and structures of fluorinated thiatriazines

Abstract Compared to trifluorotrithiatriazine A exchange of SF- by CF-groups greatly enhances the thermal stability of these ringsystems. The synthesis of B was achieved by fluorine addition to the dithiatriazine 1 via XeF 2 , C was obtained from the appropriate trichloro-derivative by metathesis with SbF 3 : Substitution of the sulfur bonded halogen by nucleophiles (e.g. silylamines) is possible without destruction of the ring system. Halide abstraction by fluoro-Lewis-acids will give stable salts, e.g. CF 3 CN 3 S 3 F + A 8 F 6 − and C 2 F 2 N 3 S + A 3 F 6 − , respectively. The structures of A - D were determined in the gas phase by electron diffraction, the bonding situation in these heterocycles is discussed with respect to increasing carbon content. The experimental results are compared with MNDO-calculations.