After most recent results in alkali metal cyclopentadienide chemistry
we succeeded in preparing two structurally different sandwich compound
s of antimony: [Cp(2)'''Sb](+) AlCl4- 1 and [Cp(2)Sb](+) AlI4- 2 (Cp'
'' = 1,2,4-tri(tert-butyl)cyclopentadienyl; Cp = pentamethylcyclopent
adienyl). The cations of 1 and 2, which are isoelectronic with stannoc
ene and similar to their lighter group homologue [Cp(2)As](+), are th
e first structurally characterized representatives of the stibocenium-
species.