The versatile reactivity of disilenides, heavier analogues of vinyl anions, opened the door to novel heavier group 14 structure motifs with residual functionalities in the periphery around the SiSi moiety. The corresponding germanium analogue, digermenide Tip 2 GeGe(Tip)Li•dme 2 (Tip = 2,4,6-triisopropylphenyl, dme = 1,2-dimethoxyethane), has now been obtained from the reduction of Tip 2 GeCl 2 with 3.3 equiv of Li powder and a catalytic amount of naphthalene in dme at −70 °C. The lithium digermenide was characterized by NMR spectroscopy, UV/vis spectroscopy, X-ray diffraction, and DFT calculations. As proof of principle for its suitability for the nucleophilic transfer of the GeGe motif, the reaction with chlorosilanes leads to the unsymmetrically substituted digermenes Tip 2 GeGe(Tip)SiR 3 .

We report the preparation of α‐chlorosilyl‐ and acyl‐substituted digermenes. Unlike the corresponding transient disilenes, these species with a Ge=Ge double bond show an unexpectedly low tendency for cyclization, but in turn are prone to thermal Ge=Ge bond cleavage. Triphenylsilyldigermene has been isolated as a crystalline model compound, and is the first fully characterized example of a neutral digermene with an A2GeGeAB substitution pattern. Spectroscopic and computational evidence prove the constitution of 1‐adamantoyldigermene as a first persistent species with a heavy double bond conjugated with a carbonyl moiety.

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A series of 4‐(dimethylamino)phenyl and pentafluorophenyl‐substituted 1,2‐bis(dimethylamino)diboranes(4) of type A, benzo‐fused cyclic 1,4‐diaza‐2,3‐diborinanes of type B, and 1,2‐diduryldiboranes(4) of type C were synthesized and structurally characterized. Spectroscopic studies revealed that the substitution pattern is a decisive factor for the observation of fluorescence in most of the derivatives A to C. For diboranes(4) of type A, unsymmetrical substitution with electron‐donating and ‐withdrawing groups at the boron centers is crucial to invoke fluorescence, albeit weak. Substitution at the boron atoms of 1,4‐diaza‐2,3‐diborinane species B leads to a modified skeletal structure. Finally, the grafting of 4‐(dimethylamino)phenyl groups to diboranes(4) of type C results in extraordinary Stokes shifts in nonpolar solvents.

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