Synthetic, spectral and structural studies of mononuclear tris(kappa(2)-amidate) aluminium complexes supported by tripodal ligands

摘要

The synthesis and characterization of mononuclear triS(kappa(2)-amidate) aluminium complexes supported by the tripodal ligands, [N(o-PhNC(O)R)(3)](3-) (R = Pr-i and Bu-t), are described. The molecular structures of [Al(N(o-PhNC(O)Pr-i)(3))] and [Al(N(o-PhNC(O)Bu-t)(3))] have been determined by X-ray diffraction studies. Both neutral six-coordinate aluminium complexes display coordination geometries that are intermediate between octahedral and trigonal prismatic. Solution-state NMR studies (H-1, C-13 and Al-27) indicate that these structures are non-fluxional in Solution. Detailed analysis of the solid-state structures shows that slight changes in the relative size of the amidate acyl substituents do not significantly impact the solid-state structures. However, large substituents may be required to prevent the formation of multinuclear species.