Organo-Zintl clusters soluble in conventional organic solvents: Setting the stage for organo-zintl cluster chemistry

Organo-Zintl cluster ions were synthesized by reactions of alkynes with Ge-9(4-) clusters in ethylenediamine. The triple bonds are hydrogenated to double bonds during the process. The resulting dialkenylated species [RHC=CHGe9CH=CHR](2-) have lower charge, their alkali-metal cations can be exchanged for tetralkylammonium cations, and the resulting compounds are soluble in nonpolar solvents. This was demostrated with [H2C=CHGe9CH=CH2](2-), which was structurally characterized with [K-(18-crown-6)](+), [Me4N](+), and [Pr4N](+) as countercations. The solubility of its salt with [OC4N](+) in various conventional organic solvents was studied.