Bond activation and catalysis are central to the development of a sustainable energy system. Frustrated Lewis Pairs have conceptually revolutionized the activation of inert chemical bonds. Far less developed are hybrid systems containing at least one transition metal as part of the electron-donating/accepting composition. These cooperative transition metal architectures present advantages over traditional systems. For instance, they incorporate, to the concept of FLPs, the movement of electron pairs as typically encountered in the elementary steps of organometallic catalysis. This Perspective presents arguably the most relevant and recent progress of a vivid field of research that aspires to implement cooperative designs in polarized transition metal systems. Moreover, it provides tools for future developments and shows that molecular control over bond-making and -breaking processes can be achieved.

Reduction of LPhSnCl with 0.66 eq. of LiBsBu3H affords the mixed-valent homocatenated tri-tin complex (LPhSn)3Cl whose HOMO primarily comprises σ-bonding along the Sn–Sn–Sn framework.

Future chemicals should preserve the efficiency of their function while reducing hazards and waste. In this context, catalysis – a fundamental pillar of Green Chemistry – is still the most effective technique capable of meeting societal requirements while offering sustainability. To further push the boundaries of catalysis and respond to these challenges, a clear understanding of the molecular level interactions is essential. To succeed, we believe it is necessary to consider the transition metal catalyst as a molecular system encompassing a local and non‐local environment. The synergistic effects that are taking place between the ligand, the metal center, and their surrounding environments primarily determine the efficiency of the bond making and breaking processes. This Concept provides tools for identifying, implementing, and combining these effects to control catalysis directly at a molecular level.

An adaptive catalytic system that provides control over the nitroarene hydrogenation network to prepare a wide range of aniline and hydroxylamine derivatives is presented. This system takes advantage of a delicate interplay between a rhodium(III) center and a Lewis acidic borane introduced in the secondary coordination sphere of the metal. The high chemoselectivity of the catalyst in the presence of various potentially vulnerable functional groups and its readiness to be deployed at a preparative scale illustrate its practicality. Mechanistic studies and density functional theory (DFT) methods were used to shed light on the mode of functioning of the catalyst and elucidate the origin of adaptivity. The competition for interaction with boron between a solvent molecule and a substrate was found crucial for adaptivity. When operating in THF, the reduction network stops at the hydroxylamine platform, whereas the reaction can be directed to the aniline platform in toluene.

An one‐pot approach to benzoxazole ring from 2‐aminophenol and aldehydes utilizing molecular sieve as the catalyst have been developed. The new oxidative cyclization reaction excluded the usage of hazardous chemical reagents, transition‐metal catalysts, chemical oxidants, or strong acids, and, therefore, reduced the production of toxic chemical waste. This offers an environmentally friendly pathway for the synthesis of various benzoxazole derivatives.

Unlike isolable tin(II) hydrides supported by bulky ligands reported in the literature, this research describes the synthesis and characterization of thermally stable tin(II) hydrides L Ph SnH (1-H) and Me LSnH (2-H) stabilized by sterically undemanding N,N,N-coordinating pincer-type ligands (L Ph = 2,5-dipyridyl-3,4-diphenylpyrrolato; Me L = 2,5-bis(6-methylpyridyl)pyrrolato). The results from previous reports reveal that attempts to access tin(II) hydrides containing less-bulky ligands have had limited success, and decomposition to tin(I) distannynes often occurs. The key to the successful isolation of 1-H and 2-H is the identification of the role of Lewis acidic B s Bu 3 , generated upon delivering hydride from commonly used hydride reagents M[B s Bu 3 H] ("selectrides", M = Li or K). This study details compelling experimental evidence and theoretical results of the role played by B s Bu 3 , which catalyzes the dehydrocoupling reactions of 1-H and 2-H to yield tin(I) distannynes L Ph Sn−SnL Ph (1 2 ) and Me LSn−Sn Me L (2 2 ) with the liberation of H 2 . To avoid the interference of B s Bu 3 , 1-H and 2-H can be isolated in pure forms using pinacolborane as the hydride donor with L Ph SnOMe (1-OMe) and Me LSnOMe (2-OMe) as reactants, respectively. DFT calculations and experimental observations indicate that the coordination of the Sn−H bond of 1-H to B s Bu 3 leaves an electrophilic tin center, rendering the nucleophilic attack by the second equivalent of 1-H forming a Sn−Sn bond.

The synthesis and coordination chemistry of Rh(i) complexes bearing a tris(isopropyl)-azaphosphatrane (TiPrAP) ligand are reported. The adaptive nature of TiPrAP ligands allows for molecular control of the immediate environment of the metal center.

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