Synthesis of Five Coordinate Spirocyclic Germanium(IV) Complexes Containing Diethanol Amine

Reaction of dihydroxo(2,2′-iminodiethanolato-AWO′) germanium(IV) (A) or dihydroxo(2,2′-methyliminodiethanolato-N,O.O′) germanium(IV) (B) with bidentate ligands, e.g. diol, α-hydroxy acid, oxalic acid, 2,6-pyridinedicarboxylic acid, or 2-aminophenol in a mixture of ethanol and xylene mixture yielded a series of unsymmetrical spiro-germanium complexes 1-6. These complexes were characterized by NMR, IR, mass spectra and elementary analysis. The ¹H NMR spectrums of all these compounds show the existence of an intramolecular N – Ge bond. X-ray analysis of compound 6 shows a short N–Ge bond (2.08 Å).