Soluble Molecular Compounds with the Mg−O−Al Structural Motif: A Model Approach for the Fixation of Organometallics on a MgO Surface

We report a facile route to the molecular compounds with the Mg−O−Al structural motif. The reaction of Mg[N(SiMe3)2]2 (1) with a stoichiometric amount of LAlOH(Me) (2) [L = CH{(CMe)(2,6-iPr2C6H3N)}2] in THF/n-hexane at 0 °C results in the formation of the heterobimetallic compound (Me3Si)2NMg(THF)2−O−Al(Me)L (3) in high yield. The similar reaction of 1 equiv of Mg[N(SiMe3)2]2 and 2 equiv of LAlOH(Me) results in the formation of trimetallic compound L(Me)Al−O−Mg(THF)2−O−Al(Me)L (4). Structural analyses of 3 and 4 have been carried out, revealing the presence of the Mg−O−Al motif. A tentative assignment of the Mg−O−Al vibrations has been made and was supported by calculations.