Derivatization of deltahedral Zintl ions by nucleophilic addition:: [Ph-Ge9-SbPh2]2- and [Ph2Sb-Ge9-Ge9-SbPh2]4-

The type of the reactions of addition of exo-bonded groups to deltahedral Zintl ions such as Ge-9(n-) has been established as addition of anionic nucleophiles. Various nucleophiles such as Ph2Bi-, Ph2Sb-, Ph- interact with the relatively low-lying LUMO of Ge-9(2-) and/or the half filled HOMO of Ge-9(3-) and bond to the clusters. The title anions, characterized in their (K-crypt) salts where crypt = 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo-[8.8.8]-hexacosane, and the previously characterized [Ph2Sb-Ge-9-SbPh2](2-) are made by a reaction of K4Ge9 with SbPh3 in ethylenediamine. [Ph-Ge-9-SbPh2](2-) is the first ogranically functionalized deltahedral Zintl ion, i.e., a deltahedral ion with a direct carbon-cluster covalent bond, that can exists without the substituents as well. The Ge-9 clusters resemble tricapped trigonal prisms with one elongated edge (one of the three edges parallel to the pseudo 3-fold axis). The two substituents are always bonded to the vertexes of such an elongated edge. The same is true for the intercluster bond in [Ph2Sb-Ge-9-Ge-9-SbPh2](4-).