Stabilized germylenes based on dialkanolamines: Synthesis, structure, chemical properties

A series of novel low valent germanium compounds RN(CHR2CR1R3O)(CHR4CHR5O)Ge 1–13 (R = Me, Ph, Bn; R1, R2, R3, R4, R5 = H, Me, Ph, (CH2)3, (CH2)4, CH2(C6H4)) was obtained via the reaction between Ge[N(SiMe3)2]2 and various dialkanolamines. All new compounds were characterized by elemental analysis, 1H and 13C NMR spectroscopy and in several cases by X-ray diffraction analysis (1, 3, 8, 10). The compounds 1, 3, 8 are dimeric in the solid state due to the formation of intermolecular Ge–O bonds, the complex 10 is monomeric, all compounds possess a transannular Ge–N bond. The reactivity of the germylenes synthesized was investigated in reactions of oxidative insertion (with halogenation reagents, MeI, disulfides), [1 + 4]-cycloaddition, oxidation and in reactions with water and acetic anhydride. Some reactions were investigated by DFT calculations.