Lanthanoiden-Komplexe, IX [1]. Reaktivitätsbestimmender Einfluß der Ligandenkonstitution bei Seltenerdamiden: Herstellung und Struktur sterisch überladener Alkoxid-Komplexe / Lanthanoid Complexes, IX [1]. Reactivity Control of Lanthanoid Amides through Ligand Effects: Synthesis and Structures of Sterically Congested Alkoxy Complexes

It is shown that the introduction of sterically demanding ligands in lanthanoid metal complexes can depend more on the precise composition of the lanthanoid precursor than on the size of the new ligand. Thus, tris(r-butyl)methanol (“rmojt-H”) does not react with the amides Ln[N(SiMe3)2]3 of the “late” (small) lanthanoid metals. However, fast and clean reactions occur with the sterically less demanding derivatives Ln[N(SiHMe2)2]3, with new homoleptic complexes Ln(tritox)3 (Ln = Y, Nd) being formed with practically all metals of this group of elements. The molecular and crystal structures of some lanthanoid amides and alkoxides are described.