Metal–Metal Bonds: From Fundamentals to Applications

Iron-based trinuclear metal-organic nanostructures on a surface with local charge accumulation

“…Higher-order polynuclear systems have also been achieved, e.g., tri- and tetra-copper coordination 15 , 17 . However, multinuclear complexes with direct metal-to-metal interactions (and their resulting properties) 8 have not been rigorously demonstrated on surfaces. A trinuclear macromolecular complex based on the coordination of a terpyridine ( tpy) -containing molecule with copper adatoms from a copper surface has been proposed 17 , but without a direct atomic-scale characterisation of the coordination motif.…”

Ambiphilic Al−Cu Bonding

“…Divergent reactivity observed with carbodiimides and CO 2 implies an ambiphilicity in the Cu-Al interaction that is dependent on the identity of the carbene co-ligand.The pursuit of unsupported metal-metal bonds has long provoked theoretical curiosity and continues to motivate some of the most striking advances in synthetic chemistry. [1,2] Aldridge and Goicoecheas landmark report of the potassium alumanyl, [K{Al(NON)}] 2 (I, where NON is the chelating tridentate ligand 4,5-bis(2,6-diisopropylanilido)-2,7-di-tertbutyl-9,9-dimethylxanthene) has spawned a variety of related species, [3][4][5][6][7][8][9] which have demonstrated their value as potent sources of nucleophilic aluminium and have been used to access several unprecedented AlÀM bonded molecules. [10][11][12] For example, the reaction of I with t Bu 3 PAuI gave rise to the two-coordinate gold complex, [(NON)AlAuP t Bu 3 ] (II).…”

Mechanistic investigations via DFT support the cooperative heterobimetallic C–H and O–H bond activation across TaIr multiple bonds

“…In recent years, there is a growing interest in transition metal catalysis for the development of heterobimetallic systems able to promote original chemical reactivity which differs from, and ideally surpasses, that of its two monometallic components. [1][2][3][4][5][6][7][8][9] Although a diverse range of heterobimetallic systems have been described to date, few of them are capable of activating substrates across the two metals simultaneously and, in many cases, the observed reactivity is localized at one metal centre only. This can be explained, in part, by the common use of sterically encumbering polyfunctional chelating ligands to drive the assembly of the two metals, which restrains the accessibility of both metal cores, therefore limiting their interest for catalysis.…”