Manganese-catalyzed hydroboration of carbon dioxide and other challenging carbonyl groups

Nature Communications, Journal Year: 2018, Volume and Issue: 9(1)

Published: Oct. 24, 2018

Reductive functionalization of the C=O unit in carboxylic acids, carbonic acid derivatives, and ultimately carbon dioxide itself is a challenging task key importance for synthesis value-added chemicals. In particular, it can open novel pathways valorization non-fossil feedstocks. Catalysts based on earth-abundant, cheap, benign metals would greatly contribute to development sustainable synthetic processes derived from this concept. Herein, manganese pincer complex [Mn(Ph2PCH2SiMe2)2NH(CO)2Br] (1) reported enable reduction broad range carbonates, even CO2 using pinacolborane as reducing agent. The shown operate under mild reaction conditions (80-120 °C), low catalyst loadings (0.1-0.2 mol%) runs solvent-less conditions. Mechanistic studies including crystallographic characterisation borane adduct imply that metal-ligand cooperation facilitates substrate activation.

Language: Английский

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Catalytic C₁ Alkylation with Methanol and Isotope‐Labeled Methanol

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 58(3), P. 775 - 779

Published: Nov. 20, 2018

Abstract A metal‐catalyzed methylation process has been developed. By employing an air‐ and moisture‐stable manganese catalyst together with isotopically labeled methanol, a series of D‐, CD 3 ‐, 13 C‐labeled products were obtained in good yields under mild reaction conditions water as the only byproduct.

Language: Английский

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Manganese Catalyzed Hydrogenation of Carbamates and Urea Derivatives

Journal of the American Chemical Society, Journal Year: 2019, Volume and Issue: 141(33), P. 12962 - 12966

Published: July 31, 2019

We report the hydrogenation of carbamates and urea derivatives, two most challenging carbonyl compounds to be hydrogenated, catalyzed for first time by a complex an earth-abundant metal. The reaction these CO2-derived compounds, manganese pincer complex, yields methanol in addition amine alcohol, which makes this methodology sustainable alternative route conversion CO2 methanol, involving base-metal catalyst. Moreover, proceeds under mild pressure (20 bar). Our observations support mechanism Mn–H complex. A plausible catalytic cycle is proposed based on informative mechanistic experiments.

Language: Английский

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Manganese(I)‐Catalyzed β‐Methylation of Alcohols Using Methanol as C₁ Source

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(1), P. 215 - 220

Published: Oct. 25, 2019

Highly selective β-methylation of alcohols was achieved using an earth-abundant first row transition metal in the air stable molecular manganese complex [Mn(CO)

Language: Английский

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Efficient catalytic conversion of terminal/internal epoxides to cyclic carbonates by porous Co(ii) MOF under ambient conditions: structure–property correlation and computational studies

Journal of Materials Chemistry A, Journal Year: 2019, Volume and Issue: 7(6), P. 2884 - 2894

Published: Jan. 1, 2019

Efficient CO₂ capture/utilization by Co(ii) MOF as a heterogeneous catalyst in CO₂–epoxide cycloaddition at ambient condition has been investigated and correlated with computational studies.

Language: Английский

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Recent Progress with Pincer Transition Metal Catalysts for Sustainability

Catalysts, Journal Year: 2020, Volume and Issue: 10(7), P. 773 - 773

Published: July 11, 2020

Our planet urgently needs sustainable solutions to alleviate the anthropogenic global warming and climate change. Homogeneous catalysis has potential play a fundamental role in this process, providing novel, efficient, at same time eco-friendly routes for both chemicals energy production. In particular, pincer-type ligation shows promising properties terms of long-term stability selectivity, as well allowing mild reaction conditions low catalyst loading. Indeed, pincer complexes have been applied plethora chemical processes, such hydrogen release, CO2 capture conversion, N2 fixation, biomass valorization synthesis high-value fuels. work, we show main advances last five years use transition metal key catalytic processes aiming more

Language: Английский

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Reversible interconversion between methanol-diamine and diamide for hydrogen storage based on manganese catalyzed (de)hydrogenation

Nature Communications, Journal Year: 2020, Volume and Issue: 11(1)

Published: Jan. 30, 2020

Abstract The development of cost-effective, sustainable, and efficient catalysts for liquid organic hydrogen carrier systems is a significant goal. However, all the reported relied on use precious metal catalysts. Herein, system based non-noble catalysis was established. Mn-catalyzed dehydrogenative coupling methanol N , ’-dimethylethylenediamine to form ’-(ethane-1,2-diyl)bis( -methylformamide), reverse hydrogenation reaction constitute storage with theoretical capacity 5.3 wt%. A rechargeable could be achieved by subsequent resulting dehydrogenation mixture regenerate H 2 -rich compound. maximum selectivity amide formation 97%.

Language: Английский

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Metal-catalyzed hydrogenation and dehydrogenation reactions for efficient hydrogen storage

Tetrahedron, Journal Year: 2020, Volume and Issue: 76(11), P. 130946 - 130946

Published: Jan. 18, 2020

Language: Английский

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Sustainable Alkylation of Nitriles with Alcohols by Manganese Catalysis

The Journal of Organic Chemistry, Journal Year: 2019, Volume and Issue: 84(12), P. 7927 - 7935

Published: May 22, 2019

A general and chemoselective catalytic alkylation of nitriles using a homogeneous nonprecious manganese catalyst is presented. This reaction uses naturally abundant alcohols readily available as coupling partners. The tolerates wide range functional groups heterocyclic moieties, efficiently providing useful cyanoalkylated products with water the only side product. Importantly, methanol can be used C1 source C-methylation achieved. mechanistic investigations support multiple role metal-ligand catalyst, dehydrogenative activation alcohol, α-C-H nitrile, hydrogenation in-situ-formed unsaturated intermediate.

Language: Английский

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Catalytic Hydrogenation of Polyurethanes to Base Chemicals: From Model Systems to Commercial and End-of-Life Polyurethane Materials

JACS Au, Journal Year: 2021, Volume and Issue: 1(4), P. 517 - 524

Published: April 6, 2021

Polyurethane (PU) is a highly valued polymer prepared from diisocyanates and polyols, it used in everyday products, such as shoe soles, mattresses, insulation materials, but also for the construction of sophisticated parts medical devices, wind turbine blades, aircrafts, spacecrafts, to name few. As PU most commonly thermoset composed cross-linked structures, its recycling complicated inefficient, leading increasing waste accumulating every year. Catalytic hydrogenation represents an atom-efficient means deconstruction polyurethanes, so far identification efficient catalyst disassembly real-life end-of-life samples has not been demonstrated. In this work, we reveal that commercially available catalyst, Ir-iPrMACHO, under 30 bar H2 150–180 °C, general effective four cornerstones PU: flexible solid, foamed, rigid isolation aromatic amines polyol fraction. For first time, variety commercial including examples foams, inline skating wheels, deconstructed into two fractions. Most desirable, our reaction conditions include use isopropyl alcohol representative green solvent. It speculated partial glycolysis at surface particles taking place solvent temperatures presence catalytic amounts base. more solubilized fragments becomes possible. isolated anilines are precursors original isocyanate building blocks, methods their conversion well-known, work reported paper provides realistic indication potential circular plastic economy solution PU. Preliminary experiments were undertaken applying Mn-iPrMACHO foam. Although successful, forcing required than those when Ir-iPrMACHO.

Language: Английский

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