Ein überraschendes Addukt einescloso-Clusters

Synthesis and Structure of 1,2-Diphenyl-1,2-disila-closo-dodecaborane(12), Reaction with [Zr(NMe2)4] and [Ta(NMe2)5]

“…In order to isolate quantitatively the dimethylamide adduct of 1 an excess of amide was used. In the case of the methyl substituted silaborane an adduct with dimethylamide and diethylamide is formed [8]. As a result of the larger phenyl substituents the closo cluster 1 is only able to form an adduct with the smaller dimethylamide nucleophile.…”

“…(Scheme 2) Hawthorne postulated the formation of an adduct between the attacking nucleophile and the closo cluster as the first step in a mechanistic sequence for the nucleophilic degradation of o-carborane [7]. In the case of 1,2-dimethyl-o-silaborane we had been able to isolate and characterize an adduct between the nucleophile diethylamide and the closo cluster 2 [8]. (Scheme 3) This adduct exhibits the structure of a closo cluster with an arachno electron household.…”