New germatranes 1–3 were synthesized by the interaction of germanium oxide with N-(2-hydroxyethyl)ethylenediamine (complex 1), N,N,N'N’-tetrakis(2-hydroxyethyl)ethylenediamine (complex 2) and N,N,N'N’-tetrakis(2-hydroxypropyl)ethylenediamine (complex 3). Their composition was confirmed by the data of elemental analysis, IR, UV/Vis and NMR spectroscopy. The thermal behavior of synthesized complexes 1–3 was studied in the temperature range 40–600 °C. The crystal structure of compound 2 was determined using single-crystal X-ray diffraction. The Hirschfeld surface analysis was performed to quantify the intermolecular contacts present within the crystal structure of complex 2. The equilibrium structures of the synthesized compounds 1–3 were calculated using DFT methods.