Yttrium-amidopyridinate complexes: Synthesis and characterization of yttrium-alkyl and yttrium-hydrido derivatives

Article abstract of DOI:10.1002/ejic.200900934

Aryl- or heteroaryl-substituted aminopyridine ligands (N₂H ^Ar) react with an equimolar amount of [Y(CH₂SiMe ₃)₃(thf)₂] to give yttrium(III)-monoalkyl complexes. The process involves the deprotonation of N₂H^Ar by a yttrium alkyl followed by a rapid and quantitative intramolecular sp ²-CH bond activation of the aryl or heteroaryl pyridine substituents. As a result, new Y complexes distinguished by rare examples of CH bond activations have been isolated and completely characterized. Selective σ-bond metathesis reactions take place on the residual Y-alky1 bonds upon treatment with PhSiH₃. Unusual binuclear metallacyclic yttrium(III)hydrido complexes have been obtained and characterized by NMR spectroscopy and X-ray diffraction analysis.