N-Heterocyclic carbene stabilized aluminium alkyls and their reactivity towards NHC-alanes

Herein, we report the synthesis of several new NHC-stabilized aluminium alkyl species [NHCAlR3] (for NHC = ICy, R = Me, iBu; NHC = IMes and IDip, R = iBu) via coordination of the respective free carbene to AlMe3 or AliBu3. Attempts to access Al-Al bonded species (dialumanes) via reactions with the respective NHCAlH3 complexes did not yield the desired Al(II) complexes via R-H elimination, instead yielding the R/H ligand scrambled complexes NHCAlR2H and NHCAlRH2, respectively. These mixed ligand species were characterized by 1H, 13C{1H} and multinuclear NMR spectroscopy, with select cases characterized by single-crystal X-ray diffraction studies.