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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Efficient Electrooxidation of 5‐Hydroxymethylfurfural Using Co‐Doped Ni₃S₂ Catalyst: Promising for H₂ Production under Industrial‐Level Current Density

Advanced Science, Journal Year: 2022, Volume and Issue: 9(17)

Published: April 15, 2022

Abstract Replacing oxygen evolution reaction (OER) by electrooxidations of organic compounds has been considered as a promising approach to enhance the energy conversion efficiency electrolytic water splitting proces. Developing efficient electrocatalysts with low potentials and high current densities is crucial for large‐scale productions H 2 other value‐added chemicals. Herein, non‐noble metal Co‐doped Ni 3 S self‐supported on foam (NF) substrate are prepared used catalysts 5‐hydroxymethylfurfural (HMF) oxidation (HMFOR) under alkaline aqueous conditions. For HMFOR, Co 0.4 NiS@NF electode achieves an extremely onset potential 0.9 V versus reversible hydrogen electrode (RHE) records large density 497 mA cm –2 at 1.45 RHE HMFOR. During HMFOR‐assisted production, yield rates 2,5‐furandicarboxylic acid (FDCA) in 10 mL electrolyte containing × −3 M HMF 330.4 µmol h –1 1000 , respectively. The electrocatalyst displays good cycling durability toward HMFOR can be electrooxidation biomass‐derived findings present facile route based heteroatom doping fabricate high‐performance catalyses that facilitate industrial‐level production coupling conventional HER cathodic processes

Language: Английский

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Advances in Selective Electrochemical Oxidation of 5‐Hydroxymethylfurfural to Produce High‐Value Chemicals

Advanced Science, Journal Year: 2022, Volume and Issue: 10(4)

Published: Dec. 8, 2022

The conversion of biomass is a favorable alternative to the fossil energy route solve crisis and environmental pollution. As one most versatile platform compounds, 5-hydroxymethylfural (HMF) can be transformed various value-added chemicals via electrolysis combining with renewable energy. Here, recent advances in electrochemical oxidation HMF, from reaction mechanism reactor design are reviewed. First, pathway summarized systematically. Second, parameters easy ignored emphasized discussed. Then, electrocatalysts reviewed comprehensively for different products reactors introduced. Finally, future efforts on exploring mechanism, electrocatalysts, prospected. This review provides deeper understanding electrocatalyst reactor, which expected promote economical efficient industrial applications.

Language: Английский

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Machine learning and chemometrics for electrochemical sensors: moving forward to the future of analytical chemistry

The Analyst, Journal Year: 2021, Volume and Issue: 146(21), P. 6351 - 6364

Published: Jan. 1, 2021

Electrochemical sensors and biosensors have been successfully used in a wide range of applications, but systematic optimization nonlinear relationships compromised for electrode fabrication data analysis. Machine learning experimental designs are chemometric tools that proved to be useful method development This minireview summarizes recent applications machine electroanalytical chemistry. First, designs, e.g., full factorial, central composite, Box-Behnken discussed as approaches optimize consider the effects from individual variables their interactions. Then, principles algorithms, including linear logistic regressions, neural network, support vector machine, introduced. These models implemented extract complex between chemical structures electrochemical properties analyze complicated improve calibration analyte classification, such electronic tongues. Lastly, future is outlined. strategies will accelerate enhance performance devices point-of-care diagnostics commercialization.

Language: Английский

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σ-Alkynyl Adsorption Enables Electrocatalytic Semihydrogenation of Terminal Alkynes with Easy-Reducible/Passivated Groups over Amorphous PdS_x Nanocapsules

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(42), P. 19456 - 19465

Published: Oct. 5, 2022

Highly chemo- and regioselective semihydrogenation of alkynes is significant challenging for the synthesis functionalized alkenes. Here, a sequential self-template method used to synthesize amorphous palladium sulfide nanocapsules (PdSx ANCs), which enables electrocatalytic terminal in H2O with excellent tolerance easily reducible groups (e.g., C–I/Br/Cl, C═O) metal center deactivating skeletons quinolyl, carboxyl, nitrile). Mechanistic studies demonstrate that specific σ-alkynyl adsorption via carbon negligible alkene on isolated Pd2+ sites ensure successful various alkenes outstanding time-irrelevant selectivity wide potential range. The key hydrogen radical intermediates are validated by electron paramagnetic resonance high-resolution mass spectrometry. Gram-scale 4-bromostyrene expedient preparation deuterated precursors drugs D2O show promising applications. Impressively, PdSx ANCs can be applied prevailing thermocatalytic alkyne using H2.

Language: Английский

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Selectivity Origin of Organic Electrosynthesis Controlled by Electrode Materials: A Case Study on Pinacols

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(14), P. 8958 - 8967

Published: July 7, 2021

Unveiling the origin of an electrode's ability to control reaction outcome and identifying key factors explore a promising electrode for selective synthesis value-added chemicals are highly desirable minimizing reliance on dominant trial-and-error screening mode materials. Here, electroreductive pinacol coupling aromatic carbonyl compounds in alkaline solution was selected as model; hydrogen adsorption free energy (ΔGH*) far from 0, specific aryl ring substrates, facile desorption products were proposed that make material ideal synthesis. These made carbon fiber paper (CP) optimal hydrobenzoin with 99% selectivity, 96% Faraday efficiency, rate 0.6 mmol cm–2 h–1. The adsorbed CP surface promoted electron transfer endowed production high selectivity over wide range potentials current densities. Furthermore, bonding also crucial reducing generating ketyl radical, intermediate pinacols, solution. could be reused 10 cycles while maintaining pinacol. This electrochemical method showcased substrate scope, which developed paired anodic fabrication benzaldehyde cathodic using bifunctional electrodes, gram-scale membrane reactor, highlighting its great promise.

Language: Английский

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Electrosynthetic Screening and Modern Optimization Strategies for Electrosynthesis of Highly Value‐added Products

ChemElectroChem, Journal Year: 2021, Volume and Issue: 8(14), P. 2621 - 2629

Published: April 19, 2021

Abstract Unlike common analytical techniques such as cyclic voltammetry, statistics‐based optimization tools are not yet often in the toolbox of preparative organic electrochemists. In general, experimental effort is optimally utilized because selection conditions based on one‐variable‐at‐a‐time principle. We will summarize statistically motivated approaches already used context electroorganic synthesis. discuss central ideas these methods which originate from other fields chemistry relation to electrosynthetic applications.

Language: Английский

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Data-driven design of new chiral carboxylic acid for construction of indoles with C-central and C–N axial chirality via cobalt catalysis

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: May 31, 2023

Challenging enantio- and diastereoselective cobalt-catalyzed C-H alkylation has been realized by an innovative data-driven knowledge transfer strategy. Harnessing the statistics of a related transformation as source, designed machine learning (ML) model took advantage delta enabled accurate extrapolative enantioselectivity predictions. Powered model, virtual screening broad scope 360 chiral carboxylic acids led to discovery new catalyst featuring intriguing furyl moiety. Further experiments verified that predicted acid can achieve excellent stereochemical control for target alkylation, which supported expedient synthesis large library substituted indoles with C-central C-N axial chirality. The reported approach provides powerful data engine accelerate molecular catalysis harnessing hidden value available structure-performance statistics.

Language: Английский

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Reaction performance prediction with an extrapolative and interpretable graph model based on chemical knowledge

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: June 15, 2023

Accurate prediction of reactivity and selectivity provides the desired guideline for synthetic development. Due to high-dimensional relationship between molecular structure function, it is challenging achieve predictive modelling transformation with required extrapolative ability chemical interpretability. To meet gap rich domain knowledge chemistry advanced graph model, herein we report a knowledge-based model that embeds digitalized steric electronic information. In addition, interaction module developed enable learning synergistic influence reaction components. this study, demonstrate achieves excellent predictions yield stereoselectivity, whose corroborated by additional scaffold-based data splittings experimental verifications new catalysts. Because embedding local environment, allows atomic level interpretation on overall performance, which serves as useful guide engineering towards target function. This offers an interpretable approach performance prediction, pointing out importance knowledge-constrained purpose.

Language: Английский

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Boosting Hydrogen Production via Selective Two‐electron Mild Electrochemical Oxidation of Tetrahydroisoquinolines Completely to Dihydroisoquinolines

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(11)

Published: Jan. 16, 2023

Different from the previous study that biomass derivatives replace water oxidation for enhancing hydrogen production, we found mild was more conductive to cathodic production. In this study, maximum Faradaic efficiency (>99 %) and lower energy consumption production achieved by precisely controlling two-electron electrochemical of tetrahydroisoquinolines (THIQs) dihydroisoquinolines (DHIQs) in place four-electron deep isoquinolines (IQs). Moreover, high value-added DHIQs were prepared THIQs with selectivity at low potential 1.36 V. Operando Raman density functional theory proved attributed regulable active species NiOOH induced interaction Co Fe preferentially breaking C-H bond rather than N-H THIQs. This novel method provides important insight into efficient biomass-assisted

Language: Английский

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