Manganese-catalyzed hydrogenation, dehydrogenation, and hydroelementation reactions

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(11), P. 4386 - 4464

Published: Jan. 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.

Language: Английский

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Structure, reactivity and catalytic properties of manganese-hydride amidate complexes

Nature Chemistry, Journal Year: 2022, Volume and Issue: 14(11), P. 1233 - 1241

Published: Sept. 12, 2022

Language: Английский

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Basic Promotors Impact Thermodynamics and Catalyst Speciation in Homogeneous Carbonyl Hydrogenation

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(18), P. 8129 - 8137

Published: April 27, 2022

Homogeneously catalyzed reactions often make use of additives and promotors that affect reactivity patterns improve catalytic performance. While the role reaction is discussed in view their chemical reactivity, we demonstrate they can be involved catalysis indirectly. In particular, adjust thermodynamics key transformations homogeneous hydrogenation enable would unfavorable otherwise. We identified this phenomenon a set well-established new Mn pincer catalysts suffer from persistent product inhibition ester hydrogenation. Although alkoxide base do not directly participate inhibitory transformations, equilibrium constants these processes. Experimentally, confirm by varying promotor concentration one control catalyst speciation inflict substantial changes to standard free energies steps cycle. Despite fact latter are universally assumed constant, state subject external control. These results suggest viewed as an integral component medium, on its own capable improving performance reshaping seemingly rigid thermodynamic landscape transformation.

Language: Английский

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Manganese(I)-catalyzed asymmetric (transfer) hydrogenation of ketones: An insight into the effect of chiral PNN and NN ligands

Journal of Catalysis, Journal Year: 2023, Volume and Issue: 418, P. 40 - 50

Published: Jan. 7, 2023

Language: Английский

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Organometallic Mn(I) Complexes in Asymmetric Catalytic (Transfer) Hydrogenation and Related Transformations

ChemCatChem, Journal Year: 2024, Volume and Issue: 16(14)

Published: March 7, 2024

Abstract Direct asymmetric hydrogenation (AH) and transfer (ATH) are among the most efficient approaches to produce chiral building blocks. Recently, these types of transformations have witnessed a shift towards use molecular catalysts based on earth‐abundant transition metals due their ready availability, economic advantage, novel properties. With particular regard manganese, catalyst development has seen both efficiency substrate scope in AH ATH greatly improved, with emergence large number well‐defined Mn‐complexes employed this field. The reaction includes C=O bonds, reduction C=N bonds reductive C=C bonds. Herein, our survey area focuses catalytic activity such complexes, versatility routes convert substrates target molecules. We consider collected findings article will be helpful reader by providing an insight into ligand design, thereby aiding future development. Moreover, review is aimed at highlighting remarkable progress made last seven years manganese complexes for enantioselective reduction.

Language: Английский

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Cycloheptyl-fused-PNN-manganese catalyzed asymmetric transfer hydrogenation of ketones

Molecular Catalysis, Journal Year: 2024, Volume and Issue: 564, P. 114274 - 114274

Published: June 8, 2024

Language: Английский

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Amino Acid Derived Chiral Aminobenzimidazole Manganese Catalysts for Asymmetric Transfer Hydrogenation of Ketones

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(13), P. 8033 - 8041

Published: June 17, 2021

A series of Mn(I) catalysts with chiral bidentate benzimidazoles derived from easily available amino acids has been developed. These types phosphine-free Mn demonstrate high activity and enantioselectivity in asymmetric transfer hydrogenation (ATH) for a broad range ketone substrates. bulkier substrate, such as 2,6-dichloro-3-fluoroacetophenone, can be converted into the drug intermediate alcohol up to 90% yield 92% ee (e.g., crizotinib). On basis experimental DFT studies, possible mechanism this Mn-catalyzed ATH is also proposed. calculations further render plausible model enantiocontrol hydrogenation, which π–π stacking interaction between catalyst substrate plays an important role.

Language: Английский

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Manganese‐Catalyzed Asymmetric Formal Hydroamination of Allylic Alcohols: A Remarkable Macrocyclic Ligand Effect

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(26)

Published: April 19, 2022

A unique family of chiral peraza N6 -macrocyclic ligands, which are conformationally rigid and have a tunable saddle-shaped cavity, is described. Utilizing their manganese(I) complexes, the first example earth-abundant transition metal-catalyzed asymmetric formal anti-Markovnikov hydroamination allylic alcohols was realized, providing practical access to synthetically important γ-amino in excellent yields enantioselectivities (up 99 % yield 98 ee). The single-crystal structure MnI complex indicates that manganese atom coordinates with dialkylamine moiety bidentate fashion. Further DFT calculations revealed five six nitrogen atoms ligand were engaged multiple noncovalent interactions Mn, an isopropanol molecule, β-amino ketone intermediate via coordination, hydrogen bonding, and/or CH⋅⋅⋅π state, showing remarkable role macrocyclic framework.

Language: Английский

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Impact of the Methylene Bridge Substitution in Chelating NHC‐Phosphine Mn(I) Catalyst for Ketone Hydrogenation

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(22)

Published: Feb. 7, 2024

Abstract Systematic modification of the chelating NHC‐phosphine ligand (NHC = N ‐heterocyclic carbene) in highly efficient ketone hydrogenation Mn(I) catalyst fac ‐[(Ph 2 PCH NHC)Mn(CO) 3 Br] has been performed and catalytic activity resulting complexes was evaluated using acetophenone as a benchmark substrate. While variation phosphine NHC moieties led to inferior results than for parent system, incorporation phenyl substituent into methylene bridge improved performance by ca . times providing maximal TON values range 15000–20000. Mechanistic investigation combining experimental computational studies allowed rationalize this beneficial effect an enhanced stabilization reaction intermediates including anionic hydride species PC(Ph)NHC)Mn(CO) H] − playing crucial role process. These highlight interest such carbon substitution strategy being rarely employed design chemically non‐innocent ligands.

Language: Английский

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The Rise of Manganese-Catalyzed Reduction Reactions

Synthesis, Journal Year: 2021, Volume and Issue: 54(03), P. 517 - 534

Published: Sept. 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

Language: Английский

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