Beschreibung:
<jats:title>Abstract</jats:title><jats:p>The synthesis of germanium(II) 2‐<jats:italic>tert</jats:italic>‐butyl‐4‐methyl‐6‐(oxidomethyl)phenolate (<jats:bold>1</jats:bold>) starting from Ge[N(SiMe<jats:sub>3</jats:sub>)<jats:sub>2</jats:sub>]<jats:sub>2</jats:sub> and the corresponding salicyl alcohol is reported. Compound <jats:bold>1</jats:bold> undergoes an intramolecular oxidative insertion reaction of germanium into a C–O bond to result in a cyclic germanium(IV) tetraoxidogermocane (<jats:bold>2</jats:bold>). Addition of 3‐<jats:italic>tert</jats:italic>‐butyl‐2‐hydroxy‐5‐methylbenzyl alcohol to either compound <jats:bold>1</jats:bold> or <jats:bold>2</jats:bold> gave a spirocyclic monoorgano dioxagermine (<jats:bold>3</jats:bold>). The results of <jats:sup>1</jats:sup>H NMR spectroscopic studies and DFT‐D calculations are in agreement with the proposed reaction cascade in which the novel germylene <jats:bold>1</jats:bold> is first converted into the germocane <jats:bold>2</jats:bold> followed by reaction with 3‐<jats:italic>tert</jats:italic>‐butyl‐2‐hydroxy‐5‐methylbenzyl alcohol to finally provide compound <jats:bold>3</jats:bold>. Addition of 4‐(dimethylamino)pyridine to a solution of germylene <jats:bold>1</jats:bold> resulted in the formation of an air‐stable monomeric 1:1 complex (<jats:bold>4</jats:bold>). The characterization of compounds <jats:bold>1</jats:bold>–<jats:bold>4</jats:bold> by single‐crystal X‐ray diffraction analysis, thermal analysis, and <jats:sup>1</jats:sup>H NMR, <jats:sup>13</jats:sup>C{<jats:sup>1</jats:sup>H} NMR, and ATR‐FTIR spectroscopy is presented.</jats:p>