Synthesis, Characterization, and Catalytic Activity of Gold Complexes Bearing Bicyclic Silicon and Germanium Anionic Ligands

Silanides ([R3Si–]) and
germanides
([R3Ge–]) are attracting attention as
donor ligands for transition metals, but their use as supporting ligands
in catalysis is limited, often due to their high reactivity. In this
study, we report the preparation and characterization of gold(I) complexes
bearing the anionic silanide and germanide ligands tmimSi– and tmimGe– (tmimH3 = tris(3-methylindol-2-yl)methane),
which are stabilized by a bicyclic cage structure. Both the silanide
and germanide complexes catalyze the hydroamination of 1-ethynyl-4-fluorobenzene
with aniline. The germanide complexes are more efficient than their
silanide analogues, likely due to their more electrophilic character.
These results show that both ligand types can be used as supporting
ligands in catalysis, which warrants further investigations.