Electrochemical Hydrogenation with Gaseous Ammonia

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 58(6), P. 1759 - 1763

Published: Dec. 14, 2018

As a carbon-free and sustainable fuel, ammonia serves as high-energy-density hydrogen-storage material. It is important to develop new reactions able utilize hydrogen source directly. Herein, we report an electrochemical hydrogenation of alkenes, alkynes, ketones using the carbon electrodes. A variety heterocycles functional groups, including for example sulfide, benzyl, benzyl carbamate, allyl carbamate were well tolerated. Fast stepwise electron transfer proton processes proposed account transformation.

Language: Английский

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Asymmetric Redox‐Polymer Interfaces for Electrochemical Reactive Separations: Synergistic Capture and Conversion of Arsenic

Advanced Materials, Journal Year: 2019, Volume and Issue: 32(6)

Published: Dec. 3, 2019

Advanced redox-polymer materials offer a powerful platform for integrating electroseparations and electrocatalysis, especially water purification environmental remediation applications. The selective capture of trivalent arsenic (As(III)) is central challenge due to its high toxicity difficulty remove at ultra-dilute concentrations. Current methods present low ion selectivity, require multistep processes transform the less harmful As(V) state. tandem conversion As(III) achieved using an asymmetric design two redox-active polymers, poly(vinyl)ferrocene (PVF) poly-TEMPO-methacrylate (PTMA). During capture, PVF selectively removes with exceptional uptake (>100 mg As/g adsorbent), during release, synergistic electrocatalytic oxidation >90% efficiency can be by PTMA, radical-based redox polymer. system demonstrates removal efficiencies real wastewater concentrations as 10 ppb. By electron-transfer through judicious redox-materials, order-of-magnitude energy increase compared non-faradaic, carbon-based materials. study first time effectiveness polymers integrated reactive separations electrochemically mediated process intensification remediation.

Language: Английский

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Electrooxidation enables highly regioselective dearomative annulation of indole and benzofuran derivatives

Nature Communications, Journal Year: 2020, Volume and Issue: 11(1)

Published: Jan. 7, 2020

Abstract The dearomatization of arenes represents a powerful synthetic methodology to provide three-dimensional chemicals high added value. Here we report general and practical protocol for regioselective dearomative annulation indole benzofuran derivatives in an electrochemical way. Under undivided electrolytic conditions, series highly functionalized five eight-membered heterocycle-2,3-fused indolines dihydrobenzofurans, which are typically unattainable under thermal can be successfully accessed yield with excellent regio- stereo-selectivity. This transformation also tolerate wide range functional groups achieve good efficiency large-scale synthesis oxidant-free conditions. In addition, cyclic voltammetry, electron paramagnetic resonance (EPR) kinetic studies indicate that the dehydrogenative annulations arise from anodic oxidation into radical cation, this process is rate-determining step.

Language: Английский

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The Application of Pulse Radiolysis to the Study of Ni(I) Intermediates in Ni-Catalyzed Cross-Coupling Reactions

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(25), P. 9332 - 9337

Published: June 15, 2021

Here we report the use of pulse radiolysis and spectroelectrochemistry to generate low-valent nickel intermediates relevant synthetically important Ni-catalyzed cross-coupling reactions interrogate their reactivities toward comproportionation oxidative addition processes. Pulse provided a direct means singly reduced [(dtbbpy)NiBr], enabling identification rapid Ni(0)/Ni(II) process taking place under electrolysis conditions. This approach also permitted measurement Ni(I) rates with electronically differentiated aryl iodide electrophiles (kOA = 1.3 × 104–2.4 105 M–1 s–1), an elementary organometallic step often proposed in nickel-catalyzed reactions. Together, these results hold implications for number

Language: Английский

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Mangana(iii/iv)electro-catalyzed C(sp³)–H azidation

Chemical Science, Journal Year: 2020, Volume and Issue: 12(8), P. 2890 - 2897

Published: Dec. 28, 2020

The merger of manganese-catalyzed C–H functionalization with electrosynthesis enabled C(sp 3 )–H azidation devoid chemical oxidants or photochemical irradiation. Detailed mechanistic studies are supportive a manganese( iii/iv ) electrocatalysis.

Language: Английский

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