Cyclothiazeno-oxo-diazidowoIframat(VI) Die Kristallstruktur von (AsPh₄)₂[W(N₃S₂)(O)(N₃)₂]₂ / Cyclothiazeno Oxodiazidotungstate(VI) The Crystal Structure of (AsPh₄)₂[W(N₃S₂)(_O)(N₃)₂]₂

Abstract

Abstract A new, improved method of synthesis for the cyclothiazeno complex AsPh 4 [WCl 4 (N 3 S 2 )] consists of the reaction of Na 2 WO 4 with molten trithiazyl chloride (NSCl) 3 followed by treatment with AsPh 4 Cl in CH 2 C 12 . Through the reaction with silver azide suspended in CH 2 C 12 in the presence of moisture, black crystalline (AsPh 4 ) 2 [W(N 3 S 2 )(O)(N 3 ) 2 ] 2 is obtained. Its IR spectrum and its crystal structure are reported. Crystal data: triclinic, space group P1̄, Z = 1, a - 1018.3, b = 1107.8, c = 1379.1 pm; a = 91.11°, β = 106.74°, γ = 113.91°. Structure determination with 3219 observed reflexions, R = 0.061. The structure consists of AsPh 4 + cations arranged to form (AsPh 4 + ) 2 pairs and of dimeric anions [W(N 3 S 2 )(O)(N 3 ) 2 ] 2⊖ in which the tungsten atom s are members of planar cyclothiazeno rings WN 3 S 2 with WN bond lengths of 186 and 222 pm. The oxygen atoms are in positions trans to the longer of these bonds. One of the N atoms of each cyclothiazeno ring is involved in the dimerization resulting in a centrosymmetric W 2 N 2 ring. The azido groups are situated above and below the ring system and complete the coordination number of six for the W atoms with WN distances of 208 and 212 pm