Strategies and mechanisms of metal–ligand cooperativity in first-row transition metal complex catalysts

Abstract

The use of metal–ligand cooperation (MLC) by transition metal bifunctional catalysts has emerged at the forefront of homogeneous catalysis science.

A Proton‐Responsive Pyridyl(benzamide)‐Functionalized NHC Ligand on Ir Complex for Alkylation of Ketones and Secondary Alcohols

“…The catalysts bearing these ligands effectively promote the reactions that involve hydride and proton management, such as (de)hydrogenation [1–11] and borrowing‐hydrogenation [12–16] . The nature (acid‐base properties) and the position/orientation of proton‐responsive unit, along with the metal‐hydricity, [17] are the key considerations to enable metal‐ligand cooperation (MLC) [18–20] for efficient hydrogen delivery/acceptance [21–24] . Among the various designs explored, the protic catalysts based on the reversible (de)protonation of −OH/=O, −CH 2 /=CH and −NH/=N motifs on pyridine, [25–27] bipyridine, [28–32] bipyrimidine [33] and azole‐pyridine/pyrimidine [34–37] are particularly effective.…”

Metal Effect Meets Volcano Plots: A DFT Study on Tris(phosphino)borane‐Transition Metal Complexes Catalyzed H2 Activation

“…[6][7][8][9] Inspired by the metal-ligand cooperation strategy, bifunctional transition metal catalysts attract more and more interest in the latest decades. [10][11][12][13][14][15][16][17] A diversity of bifunctional catalysts for H 2 activation were developed, such as Lewis base transition metal (LB-TM) catalysts and frustrated Lewis pairs (FLP) catalysts. [18][19][20][21][22][23][24] The enzyme-inspired bifunctional catalysts for H 2 activation and splitting were also reported, [25][26][27][28][29][30] which were based on the metal-ligand cooperation strategy of [FeFe]-and [NiFe]hydrogenases.…”

Mono- and Dinuclear Aluminium Complexes Derived from Biguanide and Carbothiamide Ligands

“…Furthermore, certain monoanionic ligands such as the wellestablished β-diketiminates, also called "NacNac", can be transferred to their dianionic relatives [15,16]. This behavior is beneficial in terms of metal-ligand cooperativity [17,18], and the addition of hydrogen or protic substrates to gallium(III) β-diketiminate complexes generates an additional protic side within the ligand [19,20]. During our recent studies on dianionic bis(guanidine)s [21], we were able to isolate monoprotic biguanides as well as diprotic carbothiamides depending on the experimental conditions [22], and we wondered if diprotic biguanides are available as well when using a primary instead of a secondary amine.…”