Synthetic routes to lithium, magnesium, and zinc aluminyl complexes are reported, allowing for the first structural characterization of an unsupported lithium-aluminium bond. Crystallographic and quantum-chemical studies are consistent with the presence of ah ighly polar Li À Al interaction, characterized by al ow bond order and relatively little charge transfer from Al to Li. Comparison with magnesium and zinc aluminyl systems reveals changes to both the MÀAl bond and the (NON)Al fragment (where NON = 4,5-bis(2,6-diisopropylanilido)-2,7-di-tert-butyl-9,9-dimethylxanthene), consistent with am ore covalent character,w ith the latter complex being shown to react with CO 2 via ap athway that implies that the zinc centre acts as the nucleophilic partner.