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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Multi-Functionality of Methanol in Sustainable Catalysis: Beyond Methanol Economy

ACS Catalysis, Год журнала: 2023, Номер 13(22), С. 15013 - 15053

Опубликована: Ноя. 6, 2023

Methanol is a fundamental feedstock and widely used in the chemical petroleum industries. It can serve as C1 source to make variety of C–C C–N bond formation dehydrogenative coupling products, which have important applications natural products drug discovery. A high hydrogen content (12.5 wt%) methanol makes it an effective H2 donor for transfer hydrogenation various reducible functional groups. plethora transition metal-based processes been developed using methanol. Notably, recent review articles focused on aspect However, more updated that examines challenges both C1-source H2-source organic transformations contributing concept economy has not presented yet. This Review summarizes (homogeneous, heterogeneous, photo-) catalyst system C-, N-, O-methylation ketones, alcohols, amides, nitriles, heterocyclic compounds, sulfones, amines, sulfonamides direct N-methylation nitro compounds under borrowing strategy N-formylation amines acceptorless dehydrogenation source. also covers insights into reaction mechanisms role carefully selected ligands metal catalysis activation incorporation -CD3, methylation molecules. Moreover, describes groups such aldehydes, alkynes, with detail.

Язык: Английский

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Electrocatalysis Boosts the Methanol Thermocatalytic Dehydrogenation for High-Purity H₂ and CO Production

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(14), С. 9657 - 9664

Опубликована: Апрель 1, 2024

Hydrogen production from methanol represents an energy-sustainable way to produce ethanol, but it normally results in heavy CO2 emissions. The selective conversion of into H2 and valuable chemical feedstocks offers a promising strategy; however, is limited by the harsh operating conditions low efficiency. Herein, we realize efficient high-purity CO coupling thermocatalytic dehydrogenation with electrocatalytic hydrogen oxidation on bifunctional Ru/C catalyst. Electrocatalysis enables acceleration C–H cleavage reduces partial pressure at anode, which drives equilibrium significantly enhances dehydrogenation. Furthermore, bilayer + Pd/C electrode designed mitigate poisoning facilitate oxidation. As result, high yield (558.54 mmol h–1 g–1) purity (99.9%) was achieved integrating applied cell voltage 0.4 V 200 °C, superior conventional thermal processes, main product anode. This work presents new avenue for together synthesis methanol.

Язык: Английский

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General and selective homogeneous Ru-catalyzed transfer hydrogenation, deuteration, and methylation of functional compounds using methanol

Journal of Catalysis, Год журнала: 2023, Номер 425, С. 386 - 405

Опубликована: Июнь 28, 2023

Язык: Английский

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Recycling Valuable Alkylbenzenes from Polystyrene through Methanol‐Assisted Depolymerization

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(24)

Опубликована: Апрель 8, 2024

The vast bulk of polystyrene (PS), a major type plastic polymers, ends up in landfills, which takes to thousands years decompose nature. Chemical recycling promises enable lower-energy pathways and minimal environmental impacts compared with traditional incineration mechanical recycling. Herein, we demonstrated that methanol as hydrogen supplier assisted the depolymerization PS (denoted PS-MAD) into alkylbenzenes over heterogeneous catalyst composed Ru nanoparticles on SiO

Язык: Английский

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Low-temperature thermocatalytic aqueous phase methanol reforming on Pt/defective-indium oxide

Journal of Alloys and Compounds, Год журнала: 2025, Номер 1011, С. 178458 - 178458

Опубликована: Янв. 1, 2025

Язык: Английский

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

ACS Catalysis, Год журнала: 2022, Номер 12(7), С. 3995 - 4001

Опубликована: Март 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.

Язык: Английский

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Acceptorless Dehydrogenation of Methanol to Carbon Monoxide and Hydrogen using Molecular Catalysts

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(51), С. 26500 - 26505

Опубликована: Окт. 1, 2021

The acceptorless dehydrogenation of methanol to carbon monoxide and hydrogen was investigated using homogeneous molecular complexes. Complexes ruthenium manganese comprising the MACHO ligand framework showed promising activities for this reaction. complex [RuH(CO)(BH4 )(HN(C2 H4 PPh2 )2 )] (Ru-MACHO-BH) achieved up 3150 turnovers 9230 formation at 150 °C reaching pressures 12 bar when decomposition carried out in a closed vessel. Control experiments affirmed that metal mediates initial fast formaldehyde methyl formate followed by subsequent slow decarbonylation. Depending on catalyst reaction conditions, CO/H2 ratio gas mixture thus varies over broad range from almost pure stoichiometric limit 1:2.

Язык: Английский

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Atomically Dispersed Dual Metal Sites Boost the Efficiency of Olefins Epoxidation in Tandem with CO₂ Cycloaddition

Nano Letters, Год журнала: 2022, Номер 22(20), С. 8381 - 8388

Опубликована: Сен. 20, 2022

Tandem catalysis provides an economical and energy-efficient process for the production of fine chemicals. In this work, we demonstrate that a rationally synthesized carbon-based catalyst with atomically dispersed dual Fe–Al sites (ADD-Fe-Al) achieves superior catalytic activity one-pot oxidative carboxylation olefins (conversion ∼97%, selectivity ∼91%), where yield target product over ADD-Fe-Al is at least 62% higher than monometallic counterparts. The kinetic results reveal excellent performance arises from synergistic effect between Fe (oxidation site) Al (cycloaddition site), efficient CO2 cycloaddition epoxides in presence (3.91 wt %) positively shifts oxidation equilibrium to olefin epoxidation (0.89 %). This work not only offers advanced but also opens up avenue rational design multifunctional catalysts tandem reactions future.

Язык: Английский

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Integrated Capture and Conversion of CO₂ to Methanol in a Post‐Combustion Capture Solvent: Heterogeneous Catalysts for Selective CN Bond Cleavage

Advanced Energy Materials, Год журнала: 2022, Номер 12(46)

Опубликована: Окт. 3, 2022

Abstract An efficient and selective heterogeneous catalyst is identified for the condensed‐phase hydrogenation of captured CO 2 in presence an advanced water‐lean post‐combustion capture solvent, ( N ‐(2‐EthoxyEthyl)‐3‐MorpholinoPropan‐1‐Amine), 2‐EEMPA. The catalysts commonly used gas‐phase (e.g., Cu/Zn/Al O 3 ) cause deactivation amine promoters via ‐methylation by CO cleavage formamide intermediates. A system that suppresses solvents identified, demonstrating how Pt, supported reducible metal oxides CeO or TiO , can be CN to produce methanol. This first known demonstration integrated low‐temperature thermocatalytic conversion methanol economically viable solvent. Technoeconomic analyses performed on state‐of‐technology suggest produced with a minimum selling price $4.4/gallon ($1,460/metric ton) when using from 650 MW natural gas combined cycle plant. Ultimately, road map realistic achievable improvements space velocity selectivity this process enable near cost parity fossil‐derived methanol, ≈$1.4/gal ($470/metric ton), presented.

Язык: Английский

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