Manganese-catalyzed hydrogenation, dehydrogenation, and hydroelementation reactions

Chemical Society Reviews, Год журнала: 2022, Номер 51(11), С. 4386 - 4464

Опубликована: Янв. 1, 2022

The emerging field of organometallic catalysis has shifted towards research on Earth-abundant transition metals due to their ready availability, economic advantage, and novel properties. In this case, manganese, the third most abundant transition-metal in Earth's crust, emerged as one leading competitors. Accordingly, a large number molecularly-defined Mn-complexes been synthesized employed for hydrogenation, dehydrogenation, hydroelementation reactions. regard, catalyst design is based three pillars, namely, metal-ligand bifunctionality, ligand hemilability, redox activity. Indeed, developed catalysts not only differ chelating atoms they possess but also working principles, thereby different turnover numbers product molecules. Hence, critical assessment molecularly defined manganese terms atoms, reaction conditions, mechanistic pathway, significant. Herein, we analyze complexes catalytic activity, versatility allow multiple transformations routes convert substrates target This article will be helpful get significant insight into design, aiding design.

Язык: Английский

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Recent Advances in Reversible Liquid Organic Hydrogen Carrier Systems: From Hydrogen Carriers to Catalysts

Advanced Materials, Год журнала: 2024, Номер 36(37)

Опубликована: Фев. 20, 2024

Abstract Liquid organic hydrogen carriers (LOHCs) have gained significant attention for large‐scale storage due to their remarkable gravimetric capacity (HSC) and compatibility with existing oil gas transportation networks long‐distance transport. However, the practical application of reversible LOHC systems has been constrained by intrinsic thermodynamic properties performances associated catalysts in (de)hydrogenation cycles. To overcome these challenges, thermodynamically favored carriers, high‐performance catalysts, catalytic procedures need be developed. Here, advances recent years summarized, primarily centered on regular catalyzed homogeneous heterogeneous including dehydrogenative aromatization cycloalkanes arenes N ‐heterocyclics ‐heteroarenes, as well reverse hydrogenation processes. Furthermore, development metal complexes coupling, a new family based alcohols is described that can release H 2 under relatively mild conditions. Finally, views next steps challenges field technology are provided, emphasizing resources low‐cost technologies, scenarios.

Язык: Английский

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Methanol as the Hydrogen Source in the Selective Transfer Hydrogenation of Alkynes Enabled by a Manganese Pincer Complex

Organic Letters, Год журнала: 2020, Номер 22(15), С. 6067 - 6071

Опубликована: Июль 28, 2020

The first base metal-catalyzed transfer hydrogenation of alkynes with methanol is described. An air and moisture stable manganese pincer complex catalyzes the reduction a variety different to corresponding (Z)-olefins in high yields. reaction stereo- chemoselective scalable.

Язык: Английский

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Recent Advances in Homogeneous/Heterogeneous Catalytic Hydrogenation and Dehydrogenation for Potential Liquid Organic Hydrogen Carrier (LOHC) Systems

Catalysts, Год журнала: 2021, Номер 11(12), С. 1497 - 1497

Опубликована: Дек. 9, 2021

Here, we review liquid organic hydrogen carriers (LOHCs) as a potential solution to the global warming problem due increased use of fossil fuels. Recently, molecules have attracted attention sustainable energy carrier from renewable energy-rich regions energy-deficient regions. The LOHC system is one particularly promising storage in “hydrogen economy”, and efficient mass production that generates only benign byproducts can be applied industry. Therefore, this article presents hydrogenation dehydrogenation, using homogeneous or heterogeneous catalysts, for several types LOHCs, including formic acid/formaldehyde/ammonia, homocyclic compounds, nitrogen- oxygen-containing compounds. In addition, it introduces reactor types.

Язык: Английский

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Toward a Hydrogen Economy: Development of Heterogeneous Catalysts for Chemical Hydrogen Storage and Release Reactions

ACS Energy Letters, Год журнала: 2022, Номер 7(10), С. 3734 - 3752

Опубликована: Окт. 5, 2022

Chemical hydrogen storage and release processes are essential steps for the implementation of new energy vectors. In general, individual reactions involved in such technologies need catalysts to allow discharging recharging a stable efficient manner. recent years, development materials their use renewable systems have experienced rapid growth. While many academic works this area make homogeneous catalysts, there is practical heterogeneous catalytic systems, which often can be more easily applied on larger industrial scale. Review we highlight present status using as both chemical providing detailed reaction parameters demonstration. The pros cons currently known differences relative also explained critically discussed.

Язык: Английский

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Chemoselective Hydrogenation of Nitroarenes Using an Air-Stable Base-Metal Catalyst

Organic Letters, Год журнала: 2021, Номер 23(7), С. 2742 - 2747

Опубликована: Март 23, 2021

The reduction of nitroarenes to anilines as well azobenzenes hydrazobenzenes using a single base-metal catalyst is reported. hydrogenation reactions are performed with an air-and moisture-stable manganese and proceed under relatively mild reaction conditions. transformation tolerates broad range functional groups, affording aniline derivatives in high yields. Mechanistic studies suggest that the proceeds via bifunctional activation involving metal–ligand cooperative catalysis.

Язык: Английский

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Biocarbon Supported Nanoscale Ruthenium Oxide-Based Catalyst for Clean Hydrogenation of Arenes and Heteroarenes

ACS Sustainable Chemistry & Engineering, Год журнала: 2020, Номер 8(41), С. 15740 - 15754

Опубликована: Сен. 25, 2020

Despite considerable achievements in the hydrogenation of aromatic hydrocarbons over past few years, ability to hydrogenate arene or heteroarene rings a highly selective manner presence other reducible sites without harming remaining molecular structure has long been major challenge. Such chemoselectivity and functional group tolerance is desirable for enabling direct access key building blocks polymers pharmaceutical agents. For achieving such high selectivity, development suitable catalysts central importance. Herein, we report convenient method scalable preparation ruthenium oxide (RuO2) nanoparticles supported on pine needle char (PNC) by simple impregnation salt unactivated PNC, solid byproduct (biochar) obtained slow pyrolysis biomass needles. The resulting RuO2-based nanocatalyst (RuO2@PNC) exhibited remarkable activity selectivity more than 50 challenging arenes heteroarenes, including biomass-derived compounds (e.g., 4-n-propylphenol, furfuryl alcohol, 2-methyl furan). synthetic value this transformation showcased mixture present petroleum refineries coal tars as well oils (bio-oils) with enriched furfural, ether, phenol derivatives. Under optimized conditions, performance new catalyst was compared state-of-the-art commercial Ru/C, Pd/C, Raney nickel found that RuO2@PNC superior selective. Furthermore, easily recovered reused up four cycles.

Язык: Английский

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Lanthanide/B(C₆F₅)₃-Promoted Hydroboration Reduction of Indoles and Quinolines with Pinacolborane

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(2), С. 887 - 897

Опубликована: Янв. 5, 2024

We have developed a lanthanide/B(C6F5)3-promoted hydroboration reduction of indoles and quinolines with pinacolborane (HBpin). This reaction provides streamlined access to range nitrogen-containing compounds in moderate excellent yields. Large-scale synthesis further transformations bioactive indicate that the method has potential practical applications. Preliminary mechanistic studies suggest amine additives promote formation indole-borane intermediates, proceeds via intermediates HBpin situ-formed BH3 species, followed by protodeborylation process.

Язык: Английский

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Nickel-Catalyzed Dehydrogenation of N-Heterocycles Using Molecular Oxygen

Organic Letters, Год журнала: 2020, Номер 22(16), С. 6458 - 6463

Опубликована: Авг. 12, 2020

Herein, an efficient and selective nickel-catalyzed dehydrogenation of five- six-membered N-heterocycles is presented. The transformation occurs in the presence alkyl, alkoxy, chloro, free hydroxyl primary amine, internal terminal olefin, trifluoromethyl, ester functional groups. Synthesis important ligand antimalarial drug quinine demonstrated. Mechanistic studies revealed that cyclic imine serves as key intermediate for this stepwise transformation.

Язык: Английский

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The Rise of Manganese-Catalyzed Reduction Reactions

Synthesis, Год журнала: 2021, Номер 54(03), С. 517 - 534

Опубликована: Сен. 29, 2021

Abstract Recent developments in manganese-catalyzed reducing transformations—hydrosilylation, hydroboration, hydrogenation, and transfer hydrogenation—are reviewed herein. Over the past half a decade (i.e., 2016 to present), more than 115 research publications have been reported these fields. Novel organometallic compounds new reduction transformations discovered further developed. Significant challenges that had historically acted as barriers for use of manganese catalysts reactions are slowly being broken down. This review will hopefully assist developing this area, by presenting clear concise overview catalyst structures substrate published so far. 1 Introduction 2 Hydrosilylation 3 Hydroboration 4 Hydrogenation 5 Transfer 6 Conclusion Perspective

Язык: Английский

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