Synthesis and thermal behavior of dimethyl scandium complexes featuring anilido-phosphinimine ancillary ligands

Article abstract of DOI:10.1016/j.jorganchem.2007.08.037

A family of N,N donor ligands [1-(NHAr)-2-(PR₂{double bond, long}NAr′)C₆H₄] (1a-d; Ar = 2,6-ⁱPr₂-C₆H₃, R = Me, Ph, Ar′ = 2,4,6-Me₃-C₆H₂, 2-ⁱPr-C₆H₄, 2,6-ⁱPr₂-C₆H₃) has been prepared and fully characterized by multinuclear NMR spectroscopy and X-ray crystallography. Lithiation of the N-H unit and subsequent salt metathesis protocols with ScCl₃THF₃ provides an avenue to organometallic scandium complexes. The resultant base-free monomeric dichlorides LScCl₂, 3a-d, have been fully characterized by NMR spectroscopy as well as X-ray crystallography (3a,c,d). Alkylation of the dichlorides using LiMe results in clean formation of dialkyl complexes LScMe₂ 4a-c. Thermolysis of these materials under argon and hydrogen leads to decomposition products as a result of C-H activation of the ligand. Analysis of these results provides a qualitative assessment of the metalative resistance of each ligand framework.