Lanthanoid Complexes with [(dad)Li] Ligand New Starting Materials for Organolanthanoid Chemistry

摘要

In contrast to transition metal compounds, for which the 18-e~- rule generally enables one to make a reliable statement about the relative stability, the steric saturation of the metal atom plays a decisive role for the stability of the Organolanthanoid compounds. For this reason, pentamethylcyclopentadienyl (Cp~*) and cyclopentadienyl ligands (RCp) with bulky substituents R or other known Cp equivalents employed in transition metal chemistry such as tritox (A), silox (B), scorpionate (C), or benzamidinate ligands (D) are an essential prerequisite for the preparation of most Organolanthanoid compounds. These ligands are also advantageous from a preparative point of view since their use frequently leads to highly soluble compounds.