Oligoorganogermanes: Interplay between Aryl and Trimethylsilyl Substituents

Derivatives of main group elements containing element–element bonds are characterized by unique properties due to σ-conjugation, which is an attractive subject for investigation. A novel series of digermanes, Ar(3)Ge-Ge(SiMe(3))(3), containing aryl (Ar = p-C(6)H(4)Me (1), p-C(6)H(4)F (2), C(6)F(5) (3)) and trimethylsilyl substituents, was synthesized by the reaction of germyl potassium salt, [(Me(3)Si)(3)GeK*THF], with triarylchlorogermanes, Ar(3)GeCl. The optical and electronic properties of such substituted oligoorganogermanes were investigated spectroscopically by UV/vis absorption spectroscopy and theoretically by DFT calculations. The molecular structures of compounds 1 and 2 were studied by XRD analysis. Conjugation between all structural fragments (Ge-Ge, Ge-Si, Ge-Ar, where Ar is an electron-donating or withdrawing group) was found to affect the properties.