The Bis(pentafluoroethyl)germylene Trimethylphosphane Adduct (C2F5)(2)GePMe3: Characterization, Ligand Properties, and Reactivity

Pelzer S, Neumann B, Stammler H-G, Ignat'ev N, Hoge B. The Bis(pentafluoroethyl)germylene Trimethylphosphane Adduct (C2F5)(2)GePMe3: Characterization, Ligand Properties, and Reactivity. ANGEWANDTE CHEMIE-INTERNATIONAL EDITION. 2016;55(20):6088-6092.The synthesis of the germylene phosphane adduct (C2F5)(2)GePMe3 is described. Starting from (C2F5)(3)GeH in an excess of PMe3, heating was applied, whereupon reductive elimination of C2F5H occurred. The molecular structure was ascertained by X-ray diffraction and compared with information obtained by quantum chemical methods. The ligand properties were derived by studying the IR spectrum of the nickel(0) complex [Ni(CO)(3){Ge(C2F5)(2)(PMe3)}] in the CO region. (C2F5)(2)GePMe3 turned out to be a -accepting ligand comparable to PMe3, in terms of Tolman's electronic parameter. Furthermore a [2+4] cycloaddition reaction with 2,3-dimethyl-1,3-butadiene, and sigma-bond insertion reactions were recorded. Activation of the C-Cl bond in dichloromethane gives rise to the formation of the phosphonium ylide complex [(C2F5)(2)Cl2Ge-CH2PMe3], which was fully characterized by X-ray diffraction