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

Chemical Reviews, Journal Year: 2018, Volume and Issue: 119(4), P. 2681 - 2751

Published: Dec. 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.

Language: Английский

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3d-Metal Catalyzed N- and C-Alkylation Reactions via Borrowing Hydrogen or Hydrogen Autotransfer

Chemical Reviews, Journal Year: 2018, Volume and Issue: 119(4), P. 2524 - 2549

Published: Nov. 20, 2018

The conservation of our element resources is a fundamental challenge mankind. development alcohol refunctionalization reactions possible fossil carbon strategy since alcohols can be obtained from indigestible and abundantly available biomass. rare noble metals, frequently used in key technologies such as catalysis, might feasible by replacing them with highly abundant metals. alkylation amines related C–C coupling are early examples reactions. These follow mostly the borrowing hydrogen or autotransfer catalysis concept, many 3d-metal catalysts have been disclosed recent years. In this review, we summarize progress made developing Cu, Ni, Co, Fe, Mn for C–N bond formation using concept. We expect that findings field will inspire others to develop new efficient selective earth-abundant metal applications novel mediated

Language: Английский

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Homogeneous Catalysis by Cobalt and Manganese Pincer Complexes

ACS Catalysis, Journal Year: 2018, Volume and Issue: 8(12), P. 11435 - 11469

Published: Oct. 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.

Language: Английский

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Recent advances in homogeneous borrowing hydrogen catalysis using earth-abundant first row transition metals

Organic & Biomolecular Chemistry, Journal Year: 2018, Volume and Issue: 17(7), P. 1595 - 1607

Published: Sept. 17, 2018

The review highlights the recent advances (2013-present) in use of earth-abundant first row transition metals homogeneous borrowing hydrogen catalysis. utility catalysts based on Mn, Fe, Co, Ni and Cu to promote a diverse array important C-C C-N bond forming reactions is described, including discussion reaction mechanisms, scope limitations, future challenges this burgeoning area sustainable

Language: Английский

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Homogeneous manganese-catalyzed hydrogenation and dehydrogenation reactions

Chem, Journal Year: 2020, Volume and Issue: 7(5), P. 1180 - 1223

Published: Dec. 9, 2020

Language: Английский

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

ACS Catalysis, Journal Year: 2018, Volume and Issue: 8(11), P. 10300 - 10305

Published: Oct. 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.

Language: Английский

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Manganese-Catalyzed and Base-Switchable Synthesis of Amines or Imines via Borrowing Hydrogen or Dehydrogenative Condensation

ACS Catalysis, Journal Year: 2018, Volume and Issue: 8(9), P. 8525 - 8530

Published: Aug. 8, 2018

The use of earth-abundant transition metals as a noble metal replacement in catalysis is especially interesting if different catalytic reactivity observed. We report, here, on the selective manganese-catalyzed base-switchable synthesis N-alkylated amines or imines. In both reactions, borrowing hydrogen/hydrogen autotransfer (N-alkyl amine formation) dehydrogenative condensation (imine formation), we start from same and alcohols Mn precatalyst. key presence potassium base to prefer N-alkylation sodium permit imine formation. Both bases react with manganese hydride via deprotonation. manganate reacts about 40 times faster an give corresponding than hydride. selectivity seems unique for complexes. observe broad scope complete product overlap, all alcohol combinations can be converted into N-alkyl imine, good functional group tolerance.

Language: Английский

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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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Homogeneously catalyzed acceptorless dehydrogenation of alcohols: A progress report

Coordination Chemistry Reviews, Journal Year: 2021, Volume and Issue: 443, P. 213967 - 213967

Published: May 24, 2021

Catalytic dehydrogenation of alcohols represents an attractive approach for future applications as hydrogen storage systems and clean synthesis fine chemicals. Herein, overview recent progress in homogeneously catalyzed acceptorless alcohol is presented. In Nature, efficiently by multiple metalloenzymes where a non-noble metal–ligand interplay key to activate transform substrate. We highlight the introduction multifunctional cooperative ligands coordination sphere metal center order improve catalytic activity under photochemical, electrochemical or thermal conditions. Moreover, cooperativity crucial easy transition first row based catalysis, we have seen years.

Language: Английский

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Manganese-Catalyzed β-Alkylation of Secondary Alcohols with Primary Alcohols under Phosphine-Free Conditions

ACS Catalysis, Journal Year: 2018, Volume and Issue: 8(8), P. 7201 - 7207

Published: July 5, 2018

Manganese(I) complexes bearing a pyridyl-supported pyrazolyl-imidazolyl ligand efficiently catalyzed the direct β-alkylation of secondary alcohols with primary under phosphine-free conditions. The β-alkylated were obtained in moderate to good yields water formed as byproduct through borrowing hydrogen pathway. β-Alkylation cholesterols was also effectively achieved. present protocol provides concise atom-economical method for C–C bond formation from and alcohols.

Language: Английский

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