A Surprising Adduct of acloso Cluster

Abstract

The geometry of the Si B framework remains nearly unchanged when the Si-Si edge is bridged by an electron-donating amido group. This finding is clearly evident from the single-crystal X-ray structure analysis and ab initio calculations of the uprecedented adduct that is formed by the addition of Et N to o-silaborane (structure depicted bottom right).

Oxidation of germa- and stanna-closo-dodecaborate

“…However both molecules 6 and 7 show an icosahedral twelve vertex closo geometry. 49 Obviously, the canonical Wade counting scheme fails to predict the correct cluster structures in the case of oxidized stanna-closo-dodecaborate species with main group element ligands.…”

Iodination of Stanna-closo-dodecaborate

“…30 The retention of a closo structure despite the addition of additional donor ligands is not unprecedented, and a related representative for such a behavior is the diethylamido adduct of the methylated ortho-silaborane [1,2-µ-(NEt 2 )-1,2-(Me) 2 -(Si 2 B 10 H 10 )]which maintains a closo structure but has an arachno electron count. 9 The instability of 1 at room temperature suggests that the electronic situation of the cluster is not favorable. The decomposition products could not be identified unequivocally.…”

“…Metallaboranes constitute the largest group of structurally characterized examples which deviate from Wade's rules . Recent work by Fehlner and co-workers for example lead to the isolation of a series of hypoelectronic rhenaboranes which exhibit noncanonical deltahedral structures in terms of the Wade rules. , The number of main group heteroboranes which do not obey the Wade rules is much smaller than the number of disobedient heteroboranes with transition metal vertices . It is therefore of particular interest to obtain more experimental findings for non-Wadian main group heteroborane clusters.…”

“…7,8 The number of main group heteroboranes which do not obey the Wade rules is much smaller than the number of disobedient heteroboranes with transition metal vertices. 9 It is therefore of particular interest to obtain more experimental findings for non-Wadian main group heteroborane clusters.…”