Homogeneous Catalysis for Sustainable Energy: Hydrogen and Methanol Economies, Fuels from Biomass, and Related Topics

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(1), P. 385 - 441

Published: Nov. 2, 2021

As the world pledges to significantly cut carbon emissions, demand for sustainable and clean energy has now become more important than ever. This includes both production storage of carriers, a majority which involve catalytic reactions. article reviews recent developments homogeneous catalysts in emerging applications energy. The most focus been on hydrogen as several efficient have reported recently (de)hydrogenative transformations promising economy. Another direction that extensively covered this review is methanol Homogeneous investigated from CO

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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Hydrogenation of Carboxylic Acids, Esters, and Related Compounds over Heterogeneous Catalysts: A Step toward Sustainable and Carbon-Neutral Processes

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(3), P. 1103 - 1165

Published: Jan. 5, 2023

The catalytic hydrogenation of esters and carboxylic acids represents a fundamental important class organic transformations, which is widely applied in energy, environmental, agricultural, pharmaceutical industries. Due to the low reactivity carbonyl group esters, this type reaction is, however, rather challenging. Hence, specifically active catalysts are required achieve satisfactory yield. Nevertheless, recent years, remarkable progress has been made on development for reaction, especially heterogeneous catalysts, generally dominating industry. Here review, we discuss breakthroughs as well milestone achievements industrially utilizing catalysts. In addition, related hydrogenations that considered importance cleaner energy technologies circular chemical industry will be discussed detail. Special attention paid insights into structure–activity relationship, help readers develop rational design strategies synthesis more efficient

Language: Английский

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Homogeneous Hydrogenation of CO₂ and CO to Methanol: The Renaissance of Low‐Temperature Catalysis in the Context of the Methanol Economy

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(42)

Published: Aug. 3, 2022

The traditional economy based on carbon-intensive fuels and materials has led to an exponential rise in anthropogenic CO

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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Manganese-Catalyzed Reformation of Vicinal Glycols to α-Hydroxy Carboxylic Acids with the Liberation of Hydrogen Gas

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(7), P. 3995 - 4001

Published: March 15, 2022

Conversion of readily available feedstocks to valuable platform chemicals via an eco-friendly catalytic pathway has always been one the key focuses synthetic chemists. In this context, herein, we report selective transformation feedstock, vicinal glycols, value-added α-hydroxycarboxylic acid molecules that are prevalent in bioactive and biodegradable polymers. A bench stable Earth-abundant metal complex, {[HN(C2H4PPh2)2]Mn(CO)2Br}, Mn-I catalyzed reformation reaction at low temperature high selectivity with a turnover number reaching 2400, surpassing previously used homogeneous catalysts for such reaction. Hydrogen gas is evolved as byproduct without needing acceptor. The developed protocol applicable both aromatic aliphatic delivering α-substituted hydroxycarboxylic acids yields selectivities. Detailed mechanistic studies elucidated involvements different manganese(I)-species during acceptorless dehydrogenation catalysis.

Language: Английский

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Efficient Hydrogenation of N‐Heterocycles Catalyzed by NNP–Manganese(I) Pincer Complexes at Ambient Temperature

Chemistry - A European Journal, Journal Year: 2022, Volume and Issue: 29(2)

Published: Oct. 4, 2022

Manganese-catalyzed hydrogenation reactions have aroused widespread interest in recent years. Among the catalytic systems described, especially PNP- and NNP-Mn pincer catalysts been reported for of aldehydes, ketones, nitriles, aldimines esters. Furthermore, compounds are efficient hydrogenolysis less reactive amides, ureas, carbonates, carbamates. Herein, synthesis application specific imidazolylaminophosphine ligands corresponding Mn complexes described. These new characterized studied by a combination experimental theoretical investigations, their activities tested several with good to excellent performance. Especially, reduction N-heterocycles can be performed under very mild conditions.

Language: Английский

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A Mini-Review on Syngas Fermentation to Bio-Alcohols: Current Status and Challenges

Sustainability, Journal Year: 2023, Volume and Issue: 15(4), P. 3765 - 3765

Published: Feb. 18, 2023

Biomass gasification produces syngas, mainly comprised of CO and H2 along with H2S, CO2, N2, tar compounds. Inorganic carbon present in syngas as CO2 can be utilized for the production several value-added chemicals including ethanol, higher alcohols, fuels, hydrogen. However, chemical sequestration operates at a high temperature 300–500 °C pressure 3–5 MPa presence heavy metal catalysts. Catalyst regeneration maintenance increased cost operation. Microorganisms like algae bacteria Acetobacterium Clostridium also have potential to sequester from gas phase. Research has emphasized microbial metabolites market value syngas. scale-up commercialization technology some obstacles inefficient mass transfer, contamination, inconsistency composition, requirement clean-up process. The current review summarizes recent advances utilization special consideration alcohol energy-related products challenges scale-up.

Language: Английский

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Hydrogen Activation with Ru-PN³P Pincer Complexes for the Conversion of C₁ Feedstocks

Inorganic Chemistry, Journal Year: 2024, Volume and Issue: 63(7), P. 3393 - 3401

Published: Feb. 8, 2024

The hydrogenation of C1 feedstocks (CO and CO2) has been investigated using ruthenium complexes [RuHCl(CO)(PN3P)] as the catalyst. PN3P pincer ligands containing amines in linker between central pyridine donor phosphorus donors with bulky substituents (tert-butyl (1) or TMPhos (2)) are required to obtain mononuclear single-site catalysts that can be activated by addition KOtBu generate stable five-coordinate [RuH(CO)(PN3P–H)], whereby ligand deprotonated. Activation hydrogen takes place via heterolytic cleavage [RuH2(CO)(PN3P)], but presence CO, coordination CO occurs preferentially give [RuH(CO)2(PN3P–H)]. This complex protonated cationic [RuH(CO)2(PN3P)]+, it is unable activate H2 heterolytically. In case less coordinating CO2, both 1 2 highly efficient CO2 a base (DBU), which results TON 30,000 for formation formate.

Language: Английский

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Hydrogenation of CO₂ to Methanol with Mn‐PNP‐Pincer Complexes in the Presence of Lewis Acids: the Formate Resting State Unleashed

ChemCatChem, Journal Year: 2021, Volume and Issue: 13(14), P. 3319 - 3323

Published: May 7, 2021

Abstract The hydrogenation of CO 2 to methanol was achieved using a catalytic system comprising metal complexes the form [Mn(CO) [N(C H 4 PR )] (R= i Pr/Ph, [HN(C PPh ) ]=MACHO−Ph) together with Lewis acid additives. Mechanistic studies suggest initial insertion into Mn−H bond leads formate complex as resting state. By systematically balancing interaction between acidic additive and catalyst, ligand could be removed through esterification unleash full potential. reaction conditions were optimized on basis partial order relevant compounds. combination MACHO−Ph Ti(O Pr) identified most active TON 160 ( p (CO )=5 bar, (H )=160 T =150 °C). Using solvent co‐reagent allows conversion /H in liquid phase process only substrates products.

Language: Английский

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