First-Row Transition Metal (De)Hydrogenation Catalysis Based On Functional Pincer Ligands

Chemical Reviews, Год журнала: 2018, Номер 119(4), С. 2681 - 2751

Опубликована: Дек. 31, 2018

The use of 3d metals in de/hydrogenation catalysis has emerged as a competitive field with respect to "traditional" precious metal catalyzed transformations. introduction functional pincer ligands that can store protons and/or electrons expressed by metal-ligand cooperativity and ligand redox-activity strongly stimulated this development conceptual starting point for rational catalyst design. This review aims at providing comprehensive picture the utilization first-row transition hydrogenation dehydrogenation related synthetic concepts relying on these such hydrogen borrowing methodology. Particular emphasis is put implementation relevance cooperating redox-active within mechanistic scenarios.

Язык: Английский

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Manganese Complexes for (De)Hydrogenation Catalysis: A Comparison to Cobalt and Iron Catalysts

Angewandte Chemie International Edition, Год журнала: 2017, Номер 57(1), С. 46 - 60

Опубликована: Окт. 24, 2017

The sustainable use of the resources on our planet is essential. Noble metals are very rare and diversely used in key technologies, such as catalysis. Manganese third most abundant transition metal Earth's crust based recently discovered impressive reactivity hydrogenation dehydrogenation reactions, a potentially useful noble-metal "replacement". hope novel selectivity profiles, not possible with noble metals, also an aim manganese complexes (de)hydrogenation reactions was demonstrated for first time 2016. Herein, we summarize work that has been published since then especially discuss importance homogeneous catalysts comparison to cobalt iron catalysts.

Язык: Английский

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Homogeneous Catalysis by Cobalt and Manganese Pincer Complexes

ACS Catalysis, Год журнала: 2018, Номер 8(12), С. 11435 - 11469

Опубликована: Окт. 16, 2018

Homogeneous catalysis of organic transformations by metal complexes has been mostly based on noble metals. In recent years, tremendous progress made in the field base-metal catalysis, with pincer-type complexes, such as iron, cobalt, nickel, and manganese pincer systems. Particularly impressive is explosive growth Mn-based first being reported recently 2016. This review covers homogeneously catalyzed reactions using cobalt manganese. Various are described, including acceptorless dehydrogenation, hydrogenation, dehydrogenative coupling, hydrogen borrowing, transfer, H–X additions, C–C alkene polymerization N2 fixation, their scope brief mechanistic comments.

Язык: Английский

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Manganese-Catalyzed Upgrading of Ethanol into 1-Butanol

Journal of the American Chemical Society, Год журнала: 2017, Номер 139(34), С. 11941 - 11948

Опубликована: Авг. 18, 2017

Biomass-derived ethanol is an important renewable feedstock. Its conversion into high-quality biofuels a promising route to replace fossil resources. Herein, efficient manganese-catalyzed Guerbet-type condensation reaction of form 1-butanol was explored. This the first example upgrading higher alcohols using homogeneous non-noble-metal catalyst. process proceeded selectively in presence well-defined manganese pincer complex at parts per million (ppm) level. The developed represents sustainable synthesis with excellent turnover number (>110 000) and frequency (>3000 h-1). Moreover, mechanistic studies including control experiments, NMR spectroscopy, X-ray crystallography identified essential role "N-H moiety" catalysts major intermediates related catalytic cycle.

Язык: Английский

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Isoelectronic Manganese and Iron Hydrogenation/Dehydrogenation Catalysts: Similarities and Divergences

Accounts of Chemical Research, Год журнала: 2018, Номер 51(6), С. 1558 - 1569

Опубликована: Июнь 4, 2018

ConspectusSustainable processes that utilize nontoxic, readily available, and inexpensive starting materials for organic synthesis constitute a major objective in modern chemical research. In this context, it is highly important to perform reactions under catalytic conditions replace precious metal catalysts by earth-abundant nonprecious catalysts. particular, iron manganese are promising candidates, as these among the most abundant metals earth's crust, inexpensive, exhibit low environmental impact. As far concerned, hydrogenations acceptorless alcohol dehydrogenation (AAD), sometimes conjunction with hydrogen autotransfer reactions, becoming areas of While first very synthetic process representing atom-efficient clean methodology, AAD an oxidant-free, environmentally benign reaction where carbonyl compounds together dihydrogen valuable product and/or reactant (autotransfer) water formed. Carbonyl compounds, typically generated situ, can be converted into other useful such amines, imines, or heterocycles.In 2016 several groups, including ours, discovered time potential hydride biscarbonyl Mn(I) complexes bearing strongly bound PNP pincer ligands related tridentate effective versatile hydrogenation, transfer reactions. These isoelectronic analogues respective monocarbonyl Fe(II) display similar reactivities but also quite divergent behavior depending on coligands. Moreover, show improved long-term stability high robustness toward harsh conditions. light recent achievements, Account contrasts catalysts, highlighting specific features connected particular structural electronic properties. It addresses opportunities restrictions their applications. Apart from classical hydrogenations, covers developments resulting complex molecules heterocycles via multicomponent The ambivalent hydrogen-based redox chemistry provides access variety synthetically reductive oxidative coupling Hence, cover broad scope applications activities productivities competitive those well-established knowledge about nature characteristics active Mn(I)- Fe(II)-based systems paves way conceptually mechanistically well-founded research, which might lead further discovery novel extending current limitations reactivity. underlines base beginning challenge contributes advancement waste-free sustainable catalysis.

Язык: Английский

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

Chemical Society Reviews, Год журнала: 2020, Номер 49(24), С. 8933 - 8987

Опубликована: Янв. 1, 2020

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

Язык: Английский

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Homogeneous manganese-catalyzed hydrogenation and dehydrogenation reactions

Chem, Год журнала: 2020, Номер 7(5), С. 1180 - 1223

Опубликована: Дек. 9, 2020

Язык: Английский

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General synthesis of primary amines via reductive amination employing a reusable nickel catalyst

Nature Catalysis, Год журнала: 2018, Номер 2(1), С. 71 - 77

Опубликована: Дек. 3, 2018

Язык: Английский

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Manganese-Catalyzed α-Alkylation of Ketones, Esters, and Amides Using Alcohols

ACS Catalysis, Год журнала: 2018, Номер 8(11), С. 10300 - 10305

Опубликована: Окт. 2, 2018

Herein we report the manganese-catalyzed C–C bond-forming reactions via α-alkylation of ketones, amides, and esters, using primary alcohols. β-Alkylation secondary alcohols by to obtain α-alkylated ketones is also reported. The are catalyzed a (iPr-PNP)Mn(H)(CO)2 pincer complex under mild conditions in presence (catalytic) base liberating water (and H2 case alcohol alkylation) as sole byproduct.

Язык: Английский

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Manganese-Catalyzed Aminomethylation of Aromatic Compounds with Methanol as a Sustainable C1 Building Block

Journal of the American Chemical Society, Год журнала: 2017, Номер 139(26), С. 8812 - 8815

Опубликована: Июнь 19, 2017

This study represents the first example of a manganese-catalyzed environmentally benign, practical three-component aminomethylation activated aromatic compounds including naphtols, phenols, pyridines, indoles, carbazoles, and thiophenes in combination with amines MeOH as C1 source. These reactions proceed high atom efficiency via sequence dehydrogenation condensation steps which give rise to selective C–C C–N bond formations, thereby releasing hydrogen water. A well-defined hydride Mn(I) PNP pincer complex, recently developed our laboratory, catalyzes this process very efficient way, total 28 different aminomethylated products were synthesized isolated yields up 91%. In preliminary study, related Fe(II) complex was shown catalyze methylation 2-naphtol rather than its displaying again divergent behavior isoelectronic systems.

Язык: Английский

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