The niobium oxoazides [NbO(N3)3], [NbO(N3)3·2CH3CN], [(bipy)NbO(N3)3], Cs2[NbO(N3)5] and [PPh4]2[NbO(N3)5]

Abstract

Niobium oxotriazide, [NbO(N₃)₃], was prepared in a fluoride–azide exchange reaction between [NbOF₃] and an excess of Me₃SiN₃ in SO₂ solution. In acetonitrile solution, the fluoride–azide exchange resulted in the isolation of the adduct [NbO(N₃)₃·2CH₃CN]. The subsequent reaction of [NbO(N₃)₃] with 2,2′-bipyridine (bipy) resulted in the isolation of the bipyridine adduct [(bipy)NbO(N₃)₃]. The pentaazido anion [NbO(N₃)₅]²⁻ was obtained by the reaction of [NbO(N₃)₃] with two equivalents of ionic azide. The novel niobium oxoazides were fully characterized by their vibrational spectra, impact, friction and thermal sensitivity data and, in the case of [(bipy)NbO(N₃)₃], Cs₂[NbO(N₃)₅], and [PPh₄]₂[NbO₂(N₃)₅] by their X-ray crystal structures.