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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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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Manganese Catalyzed Acceptorless Dehydrogenative Coupling Reactions

ChemCatChem, Journal Year: 2019, Volume and Issue: 12(7), P. 1891 - 1902

Published: Dec. 21, 2019

Abstract Acceptorless dehydrogenative coupling (ADC) has emerged as a powerful tool in the chemists’ arsenal for construction of various carbon‐carbon and carbon‐heteroatom bonds. These protocols are highly atom economical environmentally benign they do not require pre‐functionalized starting material produce only dihydrogen (and water) by‐product. This technique, coupled with Earths’ abundant less toxic manganese catalysis, can prove to be vital strategy generation molecular complexity from simple materials. Manganese catalyzed DHC been growing interest, low‐ high‐valent catalysts have developed. were demonstrated show excellent catalytic activity formation carbon‐carbon, bonds, cascade reactions. In this mini‐review, we would like highlight recent progress that made ADC

Language: Английский

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Synthesis of N‐Heterocycles via Oxidant‐Free Dehydrocyclization of Alcohols Using Heterogeneous Catalysts

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(48), P. 25188 - 25202

Published: June 17, 2021

N-Heterocycles, such as pyrroles, pyrimidines, quinazolines, and quinoxalines, are important building blocks for organic chemistry the fine-chemical industry. For their synthesis, catalytic borrowing hydrogen acceptorless dehydrogenative coupling reactions of alcohols sustainable reagents have received significant attention in recent years. To overcome problems product separation catalyst reusability, several metal-based heterogeneous catalysts been reported to achieve these transformations with good yields selectivity. In this Minireview, we summarize developments using both noble non-noble synthesize N-heterocycles from N-nucleophiles via dehydrogenation or methodologies. Furthermore, Minireview introduces strategies preparation functionalization corresponding catalysts, discusses reaction mechanisms roles metal electronic states, influence support Lewis acid-base properties on reactions.

Language: Английский

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Phosphine-Free Well-Defined Mn(I) Complex-Catalyzed Synthesis of Amine, Imine, and 2,3-Dihydro-1H-perimidine via Hydrogen Autotransfer or Acceptorless Dehydrogenative Coupling of Amine and Alcohol

Organometallics, Journal Year: 2019, Volume and Issue: 38(8), P. 1815 - 1825

Published: April 12, 2019

The application of nontoxic, earth-abundant transition metals in place costly noble is a paramount goal catalysis and especially interesting if the air- moisture-stable ligand scaffold used. Herein, we report synthesis amines/imines directly from alcohol amines via hydrogen autotransfer or acceptorless dehydrogenation catalyzed by well-defined phosphine-free Mn complexes. Both imines can be obtained same set alcohols using catalyst, only tuning reaction conditions. amount nature base are found to highly important aspect for observed selectivity. primary secondary have been employed as substrates N-alkylation reaction. As highlight, showed chemoselective resveratrol derivatives. Furthermore, Mn-catalyzed dehydrogenative structurally 2,3-dihydro-1H-perimidines has also demonstrated. Density functional theory calculations were carried out model path calculate profile.

Language: Английский

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Chromium‐Catalyzed Alkylation of Amines by Alcohols

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(29), P. 11789 - 11793

Published: March 18, 2020

Abstract The alkylation of amines by alcohols is a broadly applicable, sustainable, and selective method for the synthesis alkyl amines, which are important bulk fine chemicals, pharmaceuticals, agrochemicals. We show that Cr complexes can catalyze this C−N bond formation reaction. synthesized isolated 35 examples alkylated including 13 previously undisclosed products, use amino as alkylating agents was demonstrated. catalyst tolerates numerous functional groups, hydrogenation‐sensitive examples. Compared to many other alcohol‐based amine methods, where stoichiometric amount base required, our Cr‐based system gives yields higher than 90 % various with catalytic base. Our study indicates borrowing hydrogen or autotransfer reactions could thus be an alternative Fe, Co, Mn, noble metals in (de)hydrogenation catalysis.

Language: Английский

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Manganese(I)-Catalyzed Sustainable Synthesis of Quinoxaline and Quinazoline Derivatives with the Liberation of Dihydrogen

The Journal of Organic Chemistry, Journal Year: 2020, Volume and Issue: 85(11), P. 7181 - 7191

Published: May 13, 2020

Direct synthesis of N-heterocycles via the acceptorless dehydrogenative coupling is very challenging and scarcely reported under 3d transition-metal catalysis. Here, we have developed an efficient Mn(I)-catalyzed sustainable various quinoxalines from 1,2-diaminobenzenes 1,2-diols reaction. Further, this strategy was successfully applied for unprecedented quinazolines by reaction 2-aminobenzyl alcohol with primary amides. The present protocol provides atom-economical route quinoxaline quinazoline derivatives employing earth-abundant manganese salt simple phosphine-free NNN-tridentate ligand.

Language: Английский

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Recent advancement in oxidation or acceptorless dehydrogenation of alcohols to valorised products using manganese based catalysts

Coordination Chemistry Reviews, Journal Year: 2020, Volume and Issue: 411, P. 213241 - 213241

Published: March 4, 2020

Language: Английский

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Advancements in multifunctional manganese complexes for catalytic hydrogen transfer reactions

Chemical Communications, Journal Year: 2021, Volume and Issue: 57(69), P. 8534 - 8549

Published: Jan. 1, 2021

Manganese catalyzed hydrogen transfer reactions enabled net reductions and cascade CC- CN-bond formation reactions. The success is aided by multifunctional ligand design namely metal–ligand bifunctionality, hemilability, redox non-innocence.

Language: Английский

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Aromaticity in catalysis: metal ligand cooperation via ligand dearomatization and rearomatization

Chemical Communications, Journal Year: 2021, Volume and Issue: 57(25), P. 3070 - 3082

Published: Jan. 1, 2021

This feature article describes the recent conceptual understanding of aromaticity and its contribution to thermodynamics in catalytic process involving dearomatization aromatization steps via metal-ligand cooperation.

Language: Английский

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