Bis(amidinato)germylenerhodium Complexes: Synthesis, Structure, and Density Functional Theory Calculations

The first monogermylenerhodium complexes stabilized by
bulky amidinato
ligands on the divalent germanium center have been synthesized and
characterized by NMR spectroscopy and X-ray crystallography. Their
stability strongly depends on the steric hindrance of the amidinato
ligand. With trimethysilyl groups on the nitrogen atoms of the amidinato
ligand, only the germylene oxide rhodium complex could be obtained;
by contrast, with t-Bu groups, the germylenerhodium
complex was isolated. In both cases, the formation of amidinatorhodium
complexes was observed. The donating ability of the germylene ligand
has been assessed from the CO stretching frequency of the corresponding
dicarbonylrhodium complex and was confirmed by density functional
theory calculations.