Terpyridine-metal complexes: Applications in catalysis and supramolecular chemistry

Abstract

As an NNN-tridentate ligand, the 2,2':6',2"-terpyridine plays an important role in coordination chemistry. With three coordination sites and low LUMO, terpyridine and its derivatives are one of the typical Pincer ligand and/or non-innocent ligands in transition metal catalysis. Interesting catalytic reactivities have been obtained with these tpy-metal complexes targeting some challenging transformations, such as CC bond formation and hydrofunctionalization. On the other hand, terpyridine ligands can form "closed-shell" octahedral <tpy-M 2+-tpy> complexes, which provide a linear and stable linkage in supramolecular chemistry. Numerous supramolecular architectures have been achieved using modified terpyridine ligands including Sierpiński triangles, hexagonal gasket and supramolecular rosettes. This review presents a summary of recent progress regarding transition metal-terpyridine complexes with the focus on their applications in catalysis and supramolecular structure construction. Facile synthesis of terpyridine derivatives is also described. We hope this article can serve to provide some general perspectives of the terpyridine ligand and their applications in coordination chemistry.

Crystal structure of chlorido-(η 5-pentamethylcyclopentadienyl)-(4-chloro-4-pyridyl-2,2′:6′,2′′-terpyridine-κ2N,N′) rhodium(III) hexaflourophosphate, C31H29Cl2F6N3PRh

“…One of the most commonly used ligands are the nitrogen containing ligands. In organometallic chemistry, nitrogen containing ligands can coordinate with various transition metals because of the inherent lone pair of electrons [8][9][10][11][12][13]. Thus N-containing ligands are a crucial component in coordination chemistry.…”

Redox-Active Monolayers Self-Assembled on Gold Electrodes—Effect of Their Structures on Electrochemical Parameters and DNA Sensing Ability

“…The three electron-deficient pyridines make terpyridine a strong σ-donor and π-receptor. In addition, the low LUMO of terpyridine, allows this ligand to participate in redox reactions as a "non-innocent" molecule [15]. The "close shell" TPY-M(II)-TPY complexes have been widely applied by the Nishihara group for the creation of supramolecular structures of π-conjugated redox molecular wires [16,17].…”

Metal‐Terpyridine Complexes in Catalytic Application – A Spotlight on the Last Decade

“…Thereby, the electron‐density at the metal is reduced and stabilization by appropriate ligands, such as phosphines or polypyridyl systems, is required. In this context, terpyridines have been identified as versatile chelating ligands . Ciszeswki et al .…”