On the Affinity between Fullerenes and Deltahedral Zintl Ions: A UV/Vis Spectroscopic Investigation

Abstract

The close relationship of C60 and deltahedral tetrel element cluster anions has been pointed out before. We report herein on UV/Vis spectra of the Zintl anions and compounds [Ge9]2–, [(CH2=CH)2Ge9]2–, [{(Me3Si)3Si}3Ge9]–, {(Me3Si)3Si}3Ge9CH2CH3, {(Me3Si)3Si}3Ge9(CH2)2CH3, {(Me3Si)3Si}3Ge9(CH2)3CH=CH2, and [{(Me3Si)3Si}3Ge9CH2CH3]Pt(PPh3). The spectra are compared to those of the C60 fullerene, which were recorded under the same conditions. The UV/Vis spectrum of pristine [Ge9]2– resembles that of C60 and at higher concentration hint at the known trimeric [(Ge9)3]6–. The influence of ligand substitution at the Ge9 cluster‐core is highlighted. For this, the synthesis of the specifically functionalized deltahedral Ge9 clusters {(Me3Si)3Si}3Ge9(CH2)2CH3, {(Me3Si)3Si}3Ge9(CH2)2CH=CH2, and {(Me3Si)3Si}3Ge9(CH2)3C6H5 are reported for the first time and is achieved by the reaction of K[{(Me3Si)3Si}3Ge9] with the respective alkyl halides in acetonitrile. The newly synthesized products were characterized by NMR spectroscopy.