A S₈‐like [Sb₈]⁸⁻ Zintl Anion in the Ammoniate [K₁₇(Sb₈)₂(NH₂)] · 17.5NH₃

Abstract

The ammoniate [K 17 (Sb 8 ) 2 (NH 2 )] · 17.5NH 3 was synthesized by reduction of antimony with potassium in liquid ammonia. Single crystals were isolated and characterized by low temperature X-ray structure analysis. [K 17 (Sb 8 ) 2 (NH 2 )] · 17.5NH 3 crystallizes in the space group P2 1 /c (No. 14) with a ϭ 12.976 (1) Å , b ϭ 24.536(1) Å , c ϭ 22.858(1) Å and β ϭ 99.17(1)°. The ammoniate contains crown-shaped [Sb 8 ] 8Ϫ Zintl anions which are analogous 1599 to S 8 rings. The presence of amide NH 2Ϫ as an additional anion is deduced from coordination observations and the close similarity of structural features to the structure of KNH 2 .

Aromaticity and Antiaromaticity in Zintl Clusters

“…A crown‐shaped [Sb 8 ] 8− ring has been characterized in the ammoniate [K 17 (Sb 8 ) 2 (NH 2 )]⋅17.5 NH 3 , which was synthesized by a reduction of Sb with K in liquid ammonia . The S 8 ‐like ring of [Pn 8 ] 8− can act as a ligand to host a metal atom, as illustrated by the [NbAs 8 ] 3−[56] and [MoAs 8 ] 2−[57] clusters, in which the Nb 5+ and Mo 6+ ions are nested within the [As 8 ] 8− ring, respectively.…”

“…[54] Ac rown-shaped [Sb 8 ] 8À ring has been characterizedi nt he ammoniate [K 17 (Sb 8 ) 2 (NH 2 )]·17.5 NH 3 ,w hich was synthesized by ar eduction of Sb with Ki nl iquid ammonia. [55] The S 8 -like ring of [Pn 8 ] 8À can act as al igand to host am etal atom, as illustrated by the [NbAs 8 ] 3À [56] and [MoAs 8 ] 2À [57] clusters, in which the Nb 5 + and Mo 6 + ions are nestedw ithin the [As 8 ] 8À ring, respectively.P rovided that each As atom in the [As 8 ] 8À anion serves as a2 -electron s-donor,1 6-electron complexesa re expected to be formed. However, von Schneringe tal.…”

Synthesis and Structural Characterization of Magnesium‐Substituted Polystibides [(LMg)4Sb8]

“…[26] In analogy to these phosphorus compounds,t he central Sb 8 unit in 1 and 2,w hich also adopt the realgar-type homoatomic structure,c an be described as an Sb 8 4À unit ( Figure 2 ,are well known, [27] to the best of our knowledge, 1 and 2 are the first examples containing a[ Sb 8 ] 4À polyanion. [28] In addition, Breunig et al synthesized the polystibine Sb 8 [CH(SiMe 3 ) 2 ] 4 ,ametalorganic derivative containing aS b 8 core analogous to that detected for 1 and 2,b yr eduction of (SiMe 3 ) 2 HCSbCl 2 with Mg, [20] whereas von Hänisch and Nikolova successfully prepared [Sb 4 (PSiMe 2 Thex) 4 ]( Thex = CMe 2 i Pr) and [Sb 4 -(AsSi i Pr 3 ) 4 ]w ith central Sb 4 E 4 (E = P, As) realgar-type core structures. [28] In addition, Breunig et al synthesized the polystibine Sb 8 [CH(SiMe 3 ) 2 ] 4 ,ametalorganic derivative containing aS b 8 core analogous to that detected for 1 and 2,b yr eduction of (SiMe 3 ) 2 HCSbCl 2 with Mg, [20] whereas von Hänisch and Nikolova successfully prepared [Sb 4 (PSiMe 2 Thex) 4 ]( Thex = CMe 2 i Pr) and [Sb 4 -(AsSi i Pr 3 ) 4 ]w ith central Sb 4 E 4 (E = P, As) realgar-type core structures.…”

Nachweis der Löslichkeit des Acetylidions C22− – Synthese und Kristallstrukturen von K2C2⋅2 NH3, Rb2C2⋅2 NH3 und Cs2C2⋅7 NH3

“…[22] Für diese Abbildung 1. a) Kristallstruktur von K 2 C 2 ·2 NH 3 (1). [22] Für diese Abbildung 1. a) Kristallstruktur von K 2 C 2 ·2 NH 3 (1).…”

“…[1a-d] . [22] Für diese eignet sich flüssiger Ammoniak besonders gut als Lçsungsmittel, weil darin die Oxidation durch Protonen kinetisch gehemmt ist. [23] Während die Alkalimetall-Hydrogenacetylide A I C 2 H (A I = Na-Cs) gewçhnlich in flüssigem Ammoniak synthetisiert werden (siehe Experimentelles), [1a-d] sind die Alkalimetallacetylide A I 2 C 2 nur über Hochtemperaturrouten zugänglich.…”