Selective Direct Synthesis of Organofunctionalized Dialkylgermanes from Solvochemically Activated Germanium

Abstract

Kinetic inertness overcome: The selective coupling of Ge−E bonds (E=halogen, C) can be achieved at 130°C by direct synthesis from activated germanium. Alkyl bromides with an additional carbonyl function (see scheme) can be converted in a controlled manner into dibromodiorganogermanes.

Synthesis and Raman Spectroscopy of Nanoparticles of Crystalline and X‐ray Amorphous Germanium within Mesoporous SiO2

“…A thermoanalytical investigation of the orange-colored amorphous substance brings further support to the idea of (at least partial) medium range order in this material. As we already reported in previous work [23], the amorphous product shows two distinct peaks in the differential thermal analysis, an exothermal wave for cold crystallization around 490°C and an endothermal signal for melting around 909°C. Calorimetric measurements revealed that the enthalpy of cold crystallization (9.0 kJ/mol) is only about 30 % of the melting enthalpy (31.8 kJ/mol) of germanium.…”

“…For comparison with the nanoscale product, bulk amorphous hydrogenated germanium [23] was synthesized from GeCl 4 with an excess of Li[Et 3 BH] in toluene at 100°C. In contrast to the synthetic route reported previously [23], this synthesis does not require the rather expensive GeCl 2 ·dioxane as a starting material and yields a product that is free of dioxane containing impurities [24].…”

Direct Synthesis of Spin‐Crossover Complexes: An Unexpectedly Revealed New Iron‐Triazolic Structure

“…[ 25 ] Additionally, by means of direct synthesis, it is possible to obtain dialkylgermanes from germanium, which can be used as precursors for photoconducting polymers and photoresists. [ 26 ] Moreover, direct synthesis is widely used for obtaining classical commercial reagents. For example, there is a well‐known reaction of magnesium with alkyl and aryl halides in ether to produce the Grignard reagents.…”

Synthese von Germanium(I)-bromid. Ein erster Schritt zu neuen Clusterverbindungen des Germaniums?

“…Ein weiterer, in zukünftigen Arbeiten zu klärender Aspekt ist die Ähnlichkeit der Farbe von GeBr zu der des von Schlecht kürzlich vorgestellten aktivierten Germaniums, welches auf einer vollkommen anderen Syntheseroute erhalten wurde[14].Die Versuchsdurchführung erfolgt in der in Abbildung 2 angegebenen Anlage, welche über eine Öldiffusionspumpe (Balzers Diff 900) auf einen Druck von 5·10 Ϫ6 mbar evakuiert wird. Der im Zentrum der Anlage befindliche Graphitreaktor, in dem Germanium vorgelegt wurde, wird induktiv über ein hochfrequentes Wechselfeld von 1000 kHz auf 1550°C erhitzt, wobei die Ofentemperatur im unteren Drittel des Ofens mit einem Strahlungspyrometer gemessen wird (Hutter&Klüger GmbH & Co KG, Quotientenpyrometer PYROS 108).…”