Isolation and Structural Determination of a Hexacoordinated Antimony(V) Dication

Abstract

The hexacoordinated antimony(V) dication [(ppy) 3 Sb] 2 + ([1] 2 + ;p py = 2-(2-pyridyl)phenyl), stabilized by three intramolecular donor-acceptor interactions, has been isolated as itsh exachloroantimonate salt [1][SbCl 6 ] 2 ,p repared by the oxidative addition of chlorine to the neutral stibine [(ppy) 3 Sb](1), followed by the abstraction of chloride. Air-stable [1][SbCl 6 ] 2 exhibits remarkable thermal stability and the three ppy ligands on the antimony atom are shown to be magnetically inequivalent in the 1 Ha nd 13 CNMR spectra. Ah exacoordinated, meridional octahedral bonding geometry has been determined for [1][SbCl 6 ] 2 by X-ray crystallographic analysis.T heoretical calculations were performed to investigate why the meridional form was generated preferentially over the facial form. In addition, the dynamics of the ppy ligands were investigated by variable-temperature 1 HNMR spectroscopy.T he potential to generate dications by using as ingle-electron-transfer reagent has also been investigated. The dication [1] 2 + is the first [12-Sb-6] 2 + chemical speciestoh ave been structurally determined.

Isolation and characterization of bis(silylene)-stabilized antimony(I) and bismuth(I) cations

“…Cationic group 15 element compounds are valuable main group species owing to their isoelectronic relationship with the corresponding group 14 element compounds shown in Fig. 1 and their wide implications in catalysis 6 – 22 . Recently, group 15 cations of the type R 2 Pn + (Pn = P, As, Sb, Bi; R = aryl groups), cationic homologs of carbene, were described by Beckmann et al 23 – 26 .…”