Aluminum five‐ and six‐coordination in bis(acetylacetonato)aminoalkoxides

Reactions of bis(acetylacetonato)aluminum(III)‐di‐μ‐isopropoxo‐di‐isopropoxo aluminum(III), [(CH3COCHCOCH3)2Al(μ‐OPri)2Al(OPri)2] with aminoalcohols, (HORNR1R2) in 1:1 and 1:2 molar ratios in refluxing anhydrous benzene yielded binuclear complexes of the types [(CH3COCHCOCH3)2Al(μ‐OPri)2Al(ORNR1R2)(OPri)] and [(CH3COCHCOCH3)2Al(μ‐OPri)2Al(ORNR1R2)2] (R  (CH2)3, R1= R2= H; R = CH2C(CH3)2, R1= R2= H; R = (CH2)2, R1= H, R2= CH3; and R  (CH2)2, R1= R2= CH3), respectively. All these compounds are soluble in common organic solvents and exhibit sharp melting points. Molecular weight determinations reveal their binuclear nature in refluxing benzene. Plausible structures have been proposed on the basis of elemental analysis, molecular weight measurements, IR, NMR (1H, 13C, and 27Al), and FAB mass spectral studies. 27Al NMR spectra show the presence of both five‐ and six‐coordinated aluminum sites. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:518–522, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10184