Synthesis and characterization of hypercoordinated germanium complexes with hydroxyalkylethylenediamines

• Hypercoordinated germanium complexes were synthesized and characterized. • The equilibrium structures of new Ge(IV) compounds were calculated using DFT methods. • In two complexes, germanium atom is hexacoordinated, which is also confirmed by X-ray diffraction. 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.