1st Row Transition Metal Aluminylene Complexes: Preparation, Properties and Bonding Analysis
<i>The synthesis and spectroscopic characterisation of eight new first-row transition metal (M = Cr, Mn, Fe, Co, Cu) aluminylene complexes is reported. DFT and ab<b> </b>initio calculations have been used to provide detailed insight into the metal–metal bond. The σ-donation and π-backdonation properties of the aluminylene ligand are evaluated via NBO and ETS-NOCV calculations. These calculations reveal that these ligands are strong σ-donors but also competent π-acceptors. These properties are not fixed but vary in response to the nature of the transition metal centre, suggesting that aluminylene fragments can modulate their bonding to accommodate both electron-rich and electron-poor transition metals. Ab initio<b> </b>DLPNO-CCSD(T) calculations show that dispersion plays an important role in stabilising these complexes. Both short-range and long-range dispersion interactions are identified. These results will likely inform the design of next-generation catalysts based on aluminium metalloligands. </i>