Aryl Oligogermanes as Ligands for Transition Metal Complexes

The ligand properties of a series of aryl oligogermanes R₃Ge‐GeAr₃, 3–7 [Me₃Ge‐GePh₃ (3), Me₃Ge‐Ge(pTol)₃ (4), Ph₃Ge‐GePh₃ (5), (C₆F₅)₃Ge‐GePh₃ (6), Ph₃Ge‐GeMe₂GePh₃ (7)] for the synthesis of transition metal carbonyl complexes such as R₃Ge‐GeAr₂(R′C₆H₄‐η⁶)M(CO)₃ (M = Cr, 3a–7a; M = Mo, 3b; M = W, 3c) were investigated. The target complexes were obtained in moderate yields using several different synthetic approaches. The physicochemical properties of these new derivatives were investigated by IR, UV/Vis, NMR spectroscopy, electrochemistry, and DFT calculations. The molecular structures of 3c, 4a, and 5a were studied by single‐crystal X‐ray diffraction analysis. A comparative analysis of donor and acceptor properties of aryl oligogermanes as ligands for transition metal carbonyl complexes is reported.