Oligogermanes containing only electron-withdrawing substituents: Synthesis and properties

Article abstract of DOI:10.1021/acs.organomet.6b00767

A series of germanes Ar₃GeX, containing electron-withdrawing substituents [Ar = p-FC₆H₄, 1a-d, 1a (X = Cl), 1b (X = Br), 1c (X = H), 1d (X = NMe₂); p-F₃CC₆H₄, 2a-d, 2a (X = Cl), 2b (X = Br), 2c (X = H), 2d (X = NMe₂)], was synthesized and used to prepare symmetrical digermanes Ar₃Ge-GeAr₃, (p-FC₆H₄)₃GeGe(C₆H₄F-p)₃ (3), and (p-F₃CC₆H₄)₃GeGe(C₆H₄CF₃-p)₃ (4) and trigermane [(pF₃CC₆H₄)₃Ge]₂Ge(C₆F₅)2 (5) by hydrogermolysis reaction. The properties of all compounds were investigated by multinuclear NMR and for oligogermanes by UV/vis and fluorescence spectroscopy, as well as by electrochemical methods. In addition, the molecular structures of 1a, 1b, 2b, 2c, and 3-5 were studied by X-ray diffraction analysis. Compound 5 showed a significantly shifted UV/visible absorption to the red field in comparison with previously described derivatives.