Structural insights into mono-amido tris-alkyl potassium aluminates

Abstract

Co-complexation of a potassium amide with ⁱBu₃Al in the presence of the tridentate chelating ligand PMDETA results in a series of potassium aluminates of general formula [PMDETA·K(μ-amide)(μ-ⁱBu)Al(ⁱBu)₂] [where amide = TMP (6); DMP (7); HMDS (8)] which have been characterized by solution NMR spectroscopy and X-ray crystallography. Their solid-state structures contain a central KNAlC ring whose degree of puckering is dictated by the differing interactions between the potassium centre and the aluminium bound anionic ligands.