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

Chemical Society Reviews, Год журнала: 2018, Номер 47(15), С. 5786 - 5865

Опубликована: Янв. 1, 2018

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

Язык: Английский

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Electrochemical Oxidative Cross-Coupling with Hydrogen Evolution Reactions

Accounts of Chemical Research, Год журнала: 2019, Номер 52(12), С. 3309 - 3324

Опубликована: Ноя. 27, 2019

Oxidative cross-coupling has proved to be one of the most straightforward strategies for forming carbon-carbon and carbon-heteroatom bonds from easily available precursors. Over past two decades, tremendous efforts have been devoted in this field significant advances achieved. However, order remove surplus electrons substrates chemical formation, stoichiometric oxidants are usually needed. Along with development modern sustainable chemistry, considerable perform oxidative reactions under external-oxidant-free conditions. Electrochemical synthesis is a powerful environmentally benign approach, which can not only achieve cross-couplings conditions, but also release valuable hydrogen gas during bond formation. Recently, electrochemical evolution significantly explored. This Account presents our recent toward reactions. (1) We explored thiols/thiophenols arenes, heteroarenes, alkenes C-S (2) Using strategy C-H/N-H evolution, we successfully realized C-H amination phenols, anilines, imidazopyridines, even ethers. (3) Employing halide salts as green halogenating reagents, developed clean halogenation protocol oxidation To address limitation that reaction had carry out aqueous solvent, an alternative method uses CBr4, CHBr3, CH2Br2, CCl3Br, CCl4 reagents mixture acetonitrile methanol cosolvent. (4) approach constructing C-O well-developed manner. (5) Under mild C(sp2)-H C(sp3)-H phosphonylation modest high yields. (6) achieved S-H/S-H By anodic instead oxidants, overoxidation thiols thiophenols was well avoided. (7) The methods structurally diverse heterocyclic compounds were via annulations. (8) applied difunctionalization multiple step, such C-S/C-O bonds, C-S/C-N C-Se/C-O C-Se/C-N bonds. hope studies will stimulate research interest chemists pave way discovery more

Язык: Английский

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Catalyzing Electrosynthesis: A Homogeneous Electrocatalytic Approach to Reaction Discovery

Accounts of Chemical Research, Год журнала: 2020, Номер 53(3), С. 547 - 560

Опубликована: Фев. 20, 2020

Electrochemistry has been used as a tool to drive chemical reactions for over two centuries. With the help of an electrode and power source, chemists are bestowed with imaginary reagent whose potential can be precisely dialed in. The theoretically infinite redox range renders electrochemistry capable oxidizing or reducing some most tenacious compounds (e.g., F

Язык: Английский

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

Accounts of Chemical Research, Год журнала: 2019, Номер 53(1), С. 84 - 104

Опубликована: Дек. 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.

Язык: Английский

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C–H activation

Nature Reviews Methods Primers, Год журнала: 2021, Номер 1(1)

Опубликована: Июнь 17, 2021

Язык: Английский

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New Redox Strategies in Organic Synthesis by Means of Electrochemistry and Photochemistry

ACS Central Science, Год журнала: 2020, Номер 6(8), С. 1317 - 1340

Опубликована: Июль 16, 2020

As the breadth of radical chemistry grows, new means to promote and regulate single-electron redox activities play increasingly important roles in driving modern synthetic innovation. In this regard, photochemistry electrochemistry-both considered as niche fields for decades-have seen an explosive renewal interest recent years gradually have become a cornerstone organic chemistry. Outlook article, we examine current state-of-the-art areas electrochemistry photochemistry, well nascent area electrophotochemistry. These techniques employ external stimuli activate molecules imbue privileged control reaction progress selectivity that is challenging traditional chemical methods. Thus, they provide alternative entries known reactive intermediates enable distinct strategies were previously unimaginable. Of many hallmarks, electro- are often classified "green" technologies, promoting reactions under mild conditions without necessity potent wasteful oxidants reductants. This reviews most growth these with special emphasis on conceptual advances given rise enhanced accessibility tools trade.

Язык: Английский

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Intermolecular radical carboamination of alkenes

Chemical Society Reviews, Год журнала: 2020, Номер 49(6), С. 1790 - 1811

Опубликована: Янв. 1, 2020

Vicinal alkene carboamination is a highly efficient and practical synthetic strategy for the straightforward preparation of diverse valuable amine derivatives starting from simple compounds. During last decade that approach has found continuous research interests various methods have been developed using transition-metal catalysis. Driven by renaissance radical chemistry, intermolecular comprising C-C bond C-N forming step intensively investigated recently culminating in novel strategies improved protocols which complement existing methodologies. Radical can be achieved via three different reaction modes. Such cascades proceed through N-radical addition to an with subsequent formation leading 2,1-carboamination products. Alternatively, installed prior initial C-radical β-amination resulting 1,2-carboamination. The third mode comprises single electron oxidation corresponding cation gets trapped N-nucleophile cascade terminated formation. In this review, conceptual approaches will discussed examples recent literature presented. Further, reader get insights into mechanism transformations.

Язык: Английский

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Photons or Electrons? A Critical Comparison of Electrochemistry and Photoredox Catalysis for Organic Synthesis

Chemical Reviews, Год журнала: 2021, Номер 122(2), С. 2487 - 2649

Опубликована: Ноя. 9, 2021

Redox processes are at the heart of synthetic methods that rely on either electrochemistry or photoredox catalysis, but how do and catalysis compare? Both approaches provide access to high energy intermediates (e.g., radicals) enable bond formations not constrained by rules ionic 2 electron (e) mechanisms. Instead, they 1e mechanisms capable bypassing electronic steric limitations protecting group requirements, thus enabling chemists disconnect molecules in new different ways. However, while providing similar intermediates, differ several physical chemistry principles. Understanding those differences can be key designing transformations forging disconnections. This review aims highlight these similarities between comparing their underlying principles describing impact electrochemical photochemical methods.

Язык: Английский

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Reductive Electrophotocatalysis: Merging Electricity and Light To Achieve Extreme Reduction Potentials

Journal of the American Chemical Society, Год журнала: 2020, Номер 142(5), С. 2087 - 2092

Опубликована: Янв. 17, 2020

We describe a new electrophotocatalytic strategy that harnesses the power of light and electricity to generate an excited radical anion with reducing potential -3.2 V vs SCE, which can be used activate substrates very high reduction potentials (Ered ≈ -1.9 -2.9 V). The resultant aryl radicals engaged in various synthetically useful transformations furnish arylboronate, arylstannane, biaryl products.

Язык: Английский

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

Chemical Reviews, Год журнала: 2021, Номер 122(3), С. 3180 - 3218

Опубликована: Ноя. 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.

Язык: Английский

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