The synthesis of a boryl-substituted germanium(II) cation, [GeB(NDippCH)2(IPrMe)]+, (Dipp=2,6-diisopropylphenyl) featuring a supporting N-heterocyclic carbene (NHC) donor, has been explored through chloride abstraction from the corresponding (boryl)(NHC)GeCl precursor. Crystallographic studies in the solid state and UV/Vis spectra in fluorobenzene solution show that this species dimerizes under such conditions to give [(IPrMe)(HCNDipp)2BGe=GeB(NDippCH)2(IPrMe)]2+ (IPrMe = 1,3-diisopropyl-4,5-dimethylimidazolin-2-ylidene), which can be viewed as an imidazolium-functionalized digermene. The dimer is cleaved in the presence of donor solvents such as [D8]thf or [D5]pyridine, to give monomeric adducts of the type [GeB(NDippCH)2(IPrMe)(L)]+. In the case of the thf adduct, the additional donor is shown to be sufficiently labile that it can act as a convenient in situ source of the monomeric complex [GeB(NDippCH)2(IPrMe)]+ for oxidative bond-activation chemistry. Thus, [GeB(NDippCH)2(IPrMe)(thf)]+ reacts with silanes and dihydrogen, leading to the formation of GeIV products, whereas the cleavage of the N−H bond in ammonia ultimately yields products containing C−H and B−N bonds. The facile reactivity observed in E−H bond activation is in line with the very small calculated HOMO–LUMO gap (132 kJ mol−1). © 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim