Electrochemical strategies for C–H functionalization and C–N bond formation

Chemical Society Reviews, Journal Year: 2018, Volume and Issue: 47(15), P. 5786 - 5865

Published: Jan. 1, 2018

This review provides an overview of the use electrochemistry as appealing platform for expediting carbon–hydrogen functionalization and carbon–nitrogen bond formation.

Language: Английский

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Electrocatalysis as an enabling technology for organic synthesis

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(14), P. 7941 - 8002

Published: Jan. 1, 2021

Electrochemistry has recently gained increased attention as a versatile strategy for achieving challenging transformations at the forefront of synthetic organic chemistry. Electrochemistry's unique ability to generate highly reactive radical and ion intermediates in controlled fashion under mild conditions inspired development number new electrochemical methodologies preparation valuable chemical motifs. Particularly, recent developments electrosynthesis have featured an use redox-active electrocatalysts further enhance control over selective formation downstream reactivity these intermediates. Furthermore, electrocatalytic mediators enable proceed manner that is mechanistically distinct from purely methods, allowing subversion kinetic thermodynamic obstacles encountered conventional synthesis. This review highlights key innovations within past decade area electrocatalysis, with emphasis on mechanisms catalyst design principles underpinning advancements. A host oxidative reductive are discussed grouped according classification transformation nature electrocatalyst.

Language: Английский

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Recent Advances in Oxidative R¹-H/R²-H Cross-Coupling with Hydrogen Evolution via Photo-/Electrochemistry

Chemical Reviews, Journal Year: 2019, Volume and Issue: 119(12), P. 6769 - 6787

Published: May 10, 2019

Photo-/electrochemical catalyzed oxidative R1-H/R2-H cross-coupling with hydrogen evolution has become an increasingly important issue for molecular synthesis. The dream of construction C-C/C-X bonds from readily available C-H/X-H release H2 can be facilely achieved without external chemical oxidants, providing a greener model bond formation. Given the great influence these reactions in organic chemistry, we give summary state art via photo/electrochemistry, and hope this review will stimulate development synthetic strategy near future.

Language: Английский

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Electrocatalytic C–H Activation

ACS Catalysis, Journal Year: 2018, Volume and Issue: 8(8), P. 7086 - 7103

Published: June 18, 2018

C–H activation has emerged as a transformative tool in molecular synthesis, but until recently oxidative activations have largely involved the use of stoichiometric amounts expensive and toxic metal oxidants, compromising overall sustainable nature chemistry. In sharp contrast, electrochemical been identified more efficient strategy that exploits storable electricity place byproduct-generating chemical reagents. Thus, transition-metal catalysts were shown to enable versatile reactions manner. While palladium catalysis set stage for C(sp2)–H C(sp3)–H functionalizations by N-containing directing groups, rhodium ruthenium allowed weakly coordinating amides acids. contrast these precious 4d transition metals, recent year witnessed emergence cobalt oxygenations, nitrogenations, C–C-forming [4+2] alkyne annulations. Thereby, silver(I) oxidants was prevented, improving environmentally benign catalysis. Herein, we summarize major advances organometallic otherwise inert bonds electrocatalysis through May 2018.

Language: Английский

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A General Route to Prepare Low‐Ruthenium‐Content Bimetallic Electrocatalysts for pH‐Universal Hydrogen Evolution Reaction by Using Carbon Quantum Dots

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(4), P. 1718 - 1726

Published: Dec. 4, 2019

A challenging but pressing task to design and synthesize novel, efficient, robust pH-universal hydrogen evolution reaction (HER) electrocatalysts for scalable sustainable production through electrochemical water splitting. Herein, we report a facile method prepare an efficient Ru-M (M=Ni, Mn, Cu) bimetal nanoparticle carbon quantum dot hybrid (RuM/CQDs) HER. The RuNi/CQDs catalysts exhibit outstanding HER performance at all pH levels. unexpected low overpotentials of 13, 58, 18 mV shown by allow current density 10 mA cm-2 in 1 m KOH, 0.5 H2 SO4 , PBS, respectively, Ru loading 5.93 μgRu . This is among the best catalytic activities reported any platinum-free electrocatalyst. Theoretical studies reveal that Ni doping results moderate weakening bonding energy nearby surface atoms, which plays critical role improving activity.

Language: Английский

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Recent Advances in C–H Functionalization Using Electrochemical Transition Metal Catalysis

ACS Catalysis, Journal Year: 2018, Volume and Issue: 8(8), P. 7179 - 7189

Published: June 19, 2018

Electrochemical transition metal catalysis is a powerful strategy for organic synthesis because it obviates the use of stoichiometric chemical oxidants and reductants. C–H bond functionalization offers variety useful conversions simple ubiquitous molecules into diverse functional groups in single synthetic operation. This review summarizes recent progress merging electrochemistry with metal-catalyzed functionalization, specifically C–C, C–X (halogen), C–O, C–P, C–N formation.

Language: Английский

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Metalla-electrocatalyzed C–H Activation by Earth-Abundant 3d Metals and Beyond

Accounts of Chemical Research, Journal Year: 2019, Volume and Issue: 53(1), P. 84 - 104

Published: Dec. 19, 2019

To improve the efficacy of molecular syntheses, researchers wish to capitalize upon selective modification otherwise inert C-H bonds. The past two decades have witnessed considerable advances in coordination chemistry that set stage for transformative tools functionalizations. Particularly, oxidative C-H/C-H and C-H/Het-H transformations gained major attention because they avoid all elements substrate prefunctionalization. Despite advances, activations been dominated by precious transition metal catalysts based on palladium, ruthenium, iridium, rhodium, thus compromising sustainable nature overall activation approach. same holds true predominant use stoichiometric chemical oxidants regeneration active catalyst, prominently featuring hypervalent iodine(III), copper(II), silver(I) oxidants. Thereby, quantities undesired byproducts are generated, which preventive applications scale. In contrast, elegant merger homogeneous metal-catalyzed with electrosynthesis bears unique power achieve outstanding levels oxidant resource economy. Thus, contrast classical electrosyntheses control, metalla-electrocatalysis huge largely untapped potential unmet site selectivities means catalyst control. While indirect electrolysis using palladium complexes has realized, less toxic expensive base feature distinct beneficial assets toward this Account, I summarize emergence electrocatalyzed earth-abundant 3d metals beyond, a topical focus contributions from our laboratories through November 2019. cobalt electrocatalysis was identified as particularly powerful platform wealth transformations, including oxygenations nitrogenations well alkynes, alkenes, allenes, isocyanides, carbon monoxide, among others. As complementary tools, nickel, copper, very recently iron devised metalla-electrocatalyzed activations. Key success were detailed mechanistic insights, oxidation-induced reductive elimination scenarios. Likewise, development methods make weak O-coordination benefited crucial insights into catalyst's modes action experiment, operando spectroscopy, computation. Overall, thereby syntheses These electrooxidative frequently characterized improved chemoselectivities. Hence, ability dial redox at minimum level required desired transformation renders an ideal functionalization structurally complex molecules sensitive functional groups. This strategy was, inter alia, successfully applied scale-up continuous flow step-economical assembly polycyclic aromatic hydrocarbons.

Language: Английский

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Advances on the Merger of Electrochemistry and Transition Metal Catalysis for Organic Synthesis

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(3), P. 3180 - 3218

Published: Nov. 19, 2021

Synthetic organic electrosynthesis has grown in the past few decades by achieving many valuable transformations for synthetic chemists. Although electrocatalysis been popular improving selectivity and efficiency a wide variety of energy-related applications, last two decades, there much interest to develop conceptually novel transformations, selective functionalization, sustainable reactions. This review discusses recent advances combination electrochemistry homogeneous transition-metal catalysis synthesis. The enabling mechanistic studies are presented alongside advantages as well future directions address challenges metal-catalyzed electrosynthesis.

Language: Английский

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Copper-Catalyzed Electrochemical C–H Amination of Arenes with Secondary Amines

Journal of the American Chemical Society, Journal Year: 2018, Volume and Issue: 140(36), P. 11487 - 11494

Published: Aug. 30, 2018

Electrochemical oxidation represents an environmentally friendly solution to conventional methods that require caustic stoichiometric chemical oxidants. However, C–H functionalizations merging transition-metal catalysis and electrochemical techniques are, date, largely confined the use of precious metals divided cells. Herein, we report first examples copper-catalyzed aminations arenes at room temperature using undivided cells, thereby providing a practical for construction arylamines. The n-Bu4NI as redox mediator is crucial this transformation. On basis mechanistic studies including kinetic profiles, isotope effects, cyclic voltammetric analyses, radical inhibition experiments, reaction appears proceed via single-electron-transfer (SET) process, high valent Cu(III) species likely involved. These findings provide new avenue transition-metal-catalyzed functionalization reactions mediators.

Language: Английский

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Recent advances in organic electrosynthesis employing transition metal complexes as electrocatalysts

Science Bulletin, Journal Year: 2021, Volume and Issue: 66(23), P. 2412 - 2429

Published: July 13, 2021

Language: Английский

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