Electrode Materials in Modern Organic Electrochemistry

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(43), P. 18866 - 18884

Published: July 7, 2020

The choice of electrode material is critical for achieving optimal yields and selectivity in synthetic organic electrochemistry. imparts significant influence on the kinetics thermodynamics electron transfer, frequently defines success or failure a transformation. Electrode processes are complex so often empirical underlying mechanisms rationale unknown. In this review, we aim to highlight recent instances where offered, which should aid future reaction development.

Language: Английский

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

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(2), P. 2487 - 2649

Published: Nov. 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.

Language: Английский

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Synthetic Photoelectrochemistry

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(29), P. 11732 - 11747

Published: Dec. 5, 2019

Photoredox catalysis (PRC) and synthetic organic electrochemistry (SOE) are often considered competing technologies in synthesis. Their fusion has been largely overlooked. We review state-of-the-art photoelectrochemistry, grouping examples into three categories: 1) electrochemically mediated photoredox (e-PRC), 2) decoupled photoelectrochemistry (dPEC), 3) interfacial (iPEC). Such synergies prove beneficial not only for "greenness" chemical selectivity, but also the accumulation of energy accessing super-oxidizing or -reducing single electron transfer (SET) agents. Opportunities challenges this emerging exciting field discussed.

Language: Английский

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Electroreductive Carbofunctionalization of Alkenes with Alkyl Bromides via a Radical-Polar Crossover Mechanism

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(49), P. 20661 - 20670

Published: Nov. 24, 2020

Electrochemistry grants direct access to reactive intermediates (radicals and ions) in a controlled fashion toward selective organic transformations. This feature has been demonstrated variety of alkene functionalization reactions, most which proceed via an anodic oxidation pathway. In this report, we further expand the scope electrochemistry reductive alkenes. particular, strategic choice reagents reaction conditions enabled radical-polar crossover pathway wherein two distinct electrophiles can be added across highly chemo- regioselective fashion. Specifically, used strategy intermolecular carboformylation, anti-Markovnikov hydroalkylation, carbocarboxylation alkenes—reactions with rare precedents literature—by means electroreductive generation alkyl radical carbanion intermediates. These reactions employ readily available starting materials (alkyl halides, alkenes, etc.) simple, transition-metal-free display broad substrate good tolerance functional groups. A uniform protocol achieve all three transformations by simply altering medium. development provides new avenue for constructing Csp3–Csp3 bonds.

Language: Английский

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New Bisoxazoline Ligands Enable Enantioselective Electrocatalytic Cyanofunctionalization of Vinylarenes

Journal of the American Chemical Society, Journal Year: 2019, Volume and Issue: 141(37), P. 14480 - 14485

Published: Sept. 9, 2019

In contrast to the rapid growth of synthetic electrochemistry in recent years, enantioselective catalytic methods powered by electricity remain rare. this work, we report development a highly method for electrochemical cyanophosphinoylation vinylarenes. A new family serine-derived chiral bisoxazolines with ancillary coordination sites were identified as optimal ligands.

Language: Английский

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Anodic Oxidation for the Stereoselective Synthesis of Heterocycles

Accounts of Chemical Research, Journal Year: 2019, Volume and Issue: 53(1), P. 105 - 120

Published: Dec. 24, 2019

ConspectusStereodefined aliphatic heterocycles are one of the fundamental structural motifs observed in natural products and biologically active compounds. Various strategies for synthesis these building blocks based on transition metal catalysis, organocatalysis, noncatalytic conditions have been developed. Although electrosynthesis has also utilized functionalization heterocycles, stereoselective transformations under electrochemical still a challenging field electroorganic chemistry.This Account consists four main topics related to our recent efforts diastereo- and/or enantioselective especially N-heterocycles, using anodic oxidations as key steps. The first topic is development synthetic methods multisubstituted piperidines pyrrolidines from anodically prepared α-methoxy cyclic amines. Our were primarily N-acyliminium ion chemistry, diastereoselective methoxylation, arylation, deallylative methoxylation. Furthermore, we found unique property N-cyano protecting group that enabled α-methoxylation α-substituted second investigation memory chirality decarboxylative We methoxylation oxazolidine thiazolidine derivatives with appropriate N-protecting occurred stereospecific manner even though reaction proceeded through an sp2 planar carbon center. findings demonstrated example chemistry. third chiral azabicyclo-N-oxyls their application organocatalysis oxidative kinetic resolution secondary alcohols. final utilizing generated halogen cations. investigated amino alcohol bromo developed intramolecular C–C bond formation keto amides, bromoiminolactonization α-allyl malonamides, ring expansion allyl It noteworthy most reactions performed undivided cells constant-current conditions, which avoided complicated setup was beneficial large-scale reaction. In addition, some challenges hope research will contribute further construction valuable heterocyclic compounds approach.

Language: Английский

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Multicomponent reactions and photo/electrochemistry join forces: atom economy meets energy efficiency

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(6), P. 2313 - 2382

Published: Jan. 1, 2022

Visible-light photoredox catalysis has been regarded as an extremely powerful tool in organic chemistry, bringing the spotlight back to radical processes. The versatility of photocatalyzed reactions already demonstrated be effective providing alternative routes for cross-coupling well multicomponent reactions. photocatalyst allows generation high-energy intermediates through light irradiation rather than using highly reactive reagents or harsh reaction conditions. In a similar vein, electrochemistry experienced fruitful renaissance generating without need any catalyst. Such milder approaches pose basis toward higher selectivity and broader applicability. electrochemical reactions, species acts starter cascade events. This diverse reactivity use is usually not covered by classical methods. Owing availability cheaper more standardized photo- reactors, easily scalable flow-setups, it surprising that these two fields have become areas increased research interest. Keeping view, this review aimed at overview synthetic design MCRs involving and/or activation crucial step with particular focus on choice difunctionalized reagent.

Language: Английский

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Aminoxyl-Catalyzed Electrochemical Diazidation of Alkenes Mediated by a Metastable Charge-Transfer Complex

Journal of the American Chemical Society, Journal Year: 2019, Volume and Issue: 141(7), P. 2825 - 2831

Published: Jan. 23, 2019

We report the development of a new aminoxyl radical catalyst, CHAMPO, for electrochemical diazidation alkenes. Mediated by an anodically generated charge-transfer complex in form CHAMPO-N3, was achieved across broad scope alkenes without need transition metal catalyst or chemical oxidant. Mechanistic data support dual catalytic role serving as both single-electron oxidant and group transfer agent.

Language: Английский

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Recent Advances on the Electrochemical Difunctionalization of Alkenes/Alkynes

Chinese Journal of Chemistry, Journal Year: 2019, Volume and Issue: 37(3), P. 292 - 301

Published: Feb. 6, 2019

Electroorganic synthesis is an emerging area of high impact research in organic chemistry, which considered as one the green and efficient methods attracts growing attention. In this review, we summarized comprehensively recent literature reports on electrochemical oxidative difunctionalization unsaturated C—C bonds. The reaction types described review included intermolecular cyclization, intramolecular alkenes/alkynes. This focuses discussion its synthetic generality for preparation functionalized compounds related mechanism.

Language: Английский

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Electro-/photocatalytic alkene-derived radical cation chemistry: recent advances in synthetic applications

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(16), P. 7206 - 7237

Published: Jan. 1, 2022

This review covers the recent progress in electro-/photo-catalytic alkene-derived radical cation chemistry for organic synthesis, including synthetic strategies, plausible mechanisms and further research outlook.

Language: Английский

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