Synthetic, spectral and structural studies of mononuclear tris(κ2-amidate) aluminium complexes supported by tripodal ligands

The synthesis and characterization of mononuclear tris(κ2-amidate) aluminium complexes supported by the tripodal ligands, [N(o-PhNC(O)R)3]3− (R = iPr and tBu), are described. The molecular structures of [Al(N(o-PhNC(O)iPr)3)] and [Al(N(o-PhNC(O)tBu)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 (1H, 13C and 27Al) 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.

Graphical abstractThe synthesis and characterization of mononuclear tris(κ2-amidate) aluminium complexes supported by the tripodal ligands, [N(o-PhNC(O)R)3]3− (R = iPr and tBu), are described.Figure optionsDownload full-size imageDownload as PowerPoint slide