Enantioselective Nickel-Electrocatalyzed Reductive Propargylic Carboxylation with CO₂

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(21), P. 14864 - 14874

Published: May 16, 2024

The exploitation of carbon dioxide (CO2) as a sustainable, plentiful, and harmless C1 source for the catalytic synthesis enantioenriched carboxylic acids has long been acknowledged pivotal task in synthetic chemistry. Herein, we present current-driven nickel-catalyzed reductive carboxylation reaction with CO2 fixation, facilitating formation C(sp3)–C(sp2) bonds by circumventing handling moisture-sensitive organometallic reagents. This electroreductive protocol serves practical platform, paving way propargylic (up to 98% enantiomeric excess) from racemic carbonates CO2. efficacy this transformation is exemplified its successful utilization asymmetric total (S)-arundic acid, (R)-PIA, (S)-chizhine D, (S)-cochlearin G, (S,S)-alexidine, thereby underscoring potential electrosynthesis achieve complex molecular architectures sustainably.

Language: Английский

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Electrophotocatalytic hydrogenation of imines and reductive functionalization of aryl halides

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Jan. 22, 2024

Abstract The open-shell catalytically active species, like radical cations or anions, generated by one-electron transfer of precatalysts are widely used in energy-consuming redox reactions, but their excited-state lifetimes usually short. Here, a closed-shell thioxanthone-hydrogen anion species ( 3 ), which can be photochemically converted to potent and long-lived reductant, is under electrochemical conditions, enabling the electrophotocatalytic hydrogenation. Notably, TfOH regulate potential this system. In presence TfOH, precatalyst 1 ) reduction occur at low potential, so that competitive H 2 evolution inhibited, thus effectively promoting hydrogenation imines. absence reducing ability system reach potency even comparable Na 0 Li , thereby allowing hydrogenation, borylation, stannylation (hetero)arylation aryl halides construct C−H, C−B, C−Sn, C−C bonds.

Language: Английский

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Desymmetrization–Addition Reaction of Cyclopropenes to Imines via Synergistic Photoredox and Cobalt Catalysis

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(28), P. 18892 - 18898

Published: July 5, 2024

Herein, we designed a reaction for the desymmetrization-addition of cyclopropenes to imines by leveraging synergy between photoredox and asymmetric cobalt catalysis. This protocol facilitated synthesis series chiral functionalized cyclopropanes with high yield, enantioselectivity, diastereoselectivity (44 examples, up 93% yield >99% ee). A possible mechanism involving cyclopropene desymmetrization Co-H species imine addition Co-alkyl was proposed. study provides novel route important extends frontier metallaphotoredox

Language: Английский

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Molecular Photoelectrocatalysis for Radical Reactions

Accounts of Chemical Research, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 13, 2025

ConspectusMolecular photoelectrocatalysis, which combines the merits of photocatalysis and organic electrosynthesis, including their green attributes capacity to offer novel reactivity selectivity, represents an emerging field in chemistry that addresses growing demands for environmental sustainability synthetic efficiency. This synergistic approach permits access a wider range redox potentials, facilitates transformations under gentler electrode decreases use external harsh reagents. Despite these potential advantages, this area did not receive significant attention until 2019, when we others reported first examples modern molecular photoelectrocatalysis. These studies showcased immense hybrid strategy, only inherits strengths its parent fields but also unlocks unprecedented enabling challenging mild conditions while minimizing reliance on stoichiometric oxidants or reductants.In Account, present our efforts develop photoelectrocatalytic strategies leverage homogeneous catalysts facilitate diverse radical reactions. By integrating electrocatalysis with key photoinduced processes such as single electron transfer (SET), ligand-to-metal charge (LMCT), hydrogen atom (HAT), have established methods transform substrates organotrifluoroborates, arenes, carboxylic acids, alkanes into reactive intermediates. intermediates subsequently engage heteroarene C-H functionalization Importantly, photoelectrochemical catalysts, generated bulk solution readily participate efficient reactions without undergoing further overoxidation carbocations, common challenge conventional electrochemical systems.By integration photoelectrocatalysis asymmetric catalysis, developed catalysis (PEAC), proves be enantioselective synthesis chiral nitriles. involves two relay catalytic cycles: initial process engenders benzylic radicals from precursors alkyl aryl alkenes, C-radicals are then subjected cyanation subsequent copper-electrocatalytic cycle.Within realm oxidative transformations, anode serves crucial component recycling generating photocatalyst, cathode promotes proton reduction. dual functionality enables via H

Language: Английский

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Photoelectrochemical oxidative C(sp3)−H borylation of unactivated hydrocarbons

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

Published: Oct. 16, 2023

Organoboron compounds are of high significance in organic synthesis due to the unique versatility boryl substituents access further modifications. The demand for incorporation moieties into molecular structures has witnessed significant progress, particularly C(sp3)-H borylation hydrocarbons. Taking advantage special characteristics photo/electrochemistry, we herein describe development an oxidative reaction under metal- and oxidant-free conditions, enabled by photoelectrochemical strategy. exhibits broad substrate scope (>57 examples), includes use simple alkanes, halides, silanes, ketones, esters nitriles as viable substrates. Notably, unconventional regioselectivity is achieved, with coupling site selectively located distal methyl group. Our method operationally easily scalable, offers a feasible approach one-step high-value organoboron building blocks from hydrocarbons, which would provide ample opportunities drug discovery.

Language: Английский

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Electrophotocatalytic tri- or difluoromethylative cyclization of alkenes

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(10), P. 2482 - 2490

Published: Jan. 1, 2023

Photoelectrocatalysis is mild yet potent and this work unlocks the potential of unactivated alkenes for oxidant-free oxidative cyclization alkenes.

Language: Английский

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Electrophotochemical Metal‐Catalyzed Enantioselective Decarboxylative Cyanation

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 29(24)

Published: Jan. 13, 2023

Abstract In contrast to the rapid growth of electrophotocatalysis in recent years, enantioselective catalytic reactions powered by this unique methodology remain rare. work, we report an electrophotochemical metal‐catalyzed protocol for direct asymmetric decarboxylative cyanation aliphatic carboxylic acids. The synergistic merging cerium catalysis and electrochemical copper permits mild reaction conditions formation utilization key carbon centered radicals combining power light electrical energy. Electrophotochemical enables radical decarboxylation produce alkyl radicals, which could be effectively intercepted construction C−CN bonds a highly stereoselective fashion. This environmentally benign method smoothly converts diverse array arylacetic acids into corresponding nitriles good yields enantioselectivities without using chemical oxidants or pre‐functionalization acid substrates can readily scaled up.

Language: Английский

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Selective C(sp3)–H arylation/alkylation of alkanes enabled by paired electrocatalysis

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

Published: Dec. 2, 2023

We report a combination of electrocatalysis and photoredox catalysis to perform selective C(sp3)-H arylation/alkylation alkanes, in which binary catalytic system based on earth-abundant iron nickel is applied. Reaction selectivity between two-component arylation three-component alkylation tuned by modulating the applied current light source. Importantly, an ultra-low anodic potential (~0.23 V vs. Ag/AgCl) this protocol, thus enabling compatibility with variety functional groups (>70 examples). The robustness method further demonstrated preparative scale late-stage diversification natural products pharmaceutical derivatives.

Language: Английский

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Photoredox catalysis harvesting multiple photon or electrochemical energies

Beilstein Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 19, P. 1055 - 1145

Published: July 28, 2023

Photoredox catalysis (PRC) is a cutting-edge frontier for single electron-transfer (SET) reactions, enabling the generation of reactive intermediates both oxidative and reductive processes via photon activation catalyst. Although this represents significant step towards chemoselective and, more generally, sustainable chemistry, its efficacy limited by energy visible light photons. Nowadays, excellent alternative conditions are available to overcome these limitations, harvesting two different but correlated concepts: use multi-photon such as consecutive photoinduced electron transfer (conPET) combination photo- electrochemistry in synthetic photoelectrochemistry (PEC). Herein, we review most recent contributions fields activations organic functional groups. New opportunities chemists captured, selective reactions employing super-oxidants super-reductants engage unactivated chemical feedstocks, scalability up gram scales continuous flow. This provides comparisons between techniques (multi-photon photoredox PEC) help reader fully understand their similarities, differences potential applications therefore choose which method appropriate given reaction, scale purpose project.

Language: Английский

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Asymmetric Paired Electrocatalysis: Enantioselective Olefin–Sulfonylimine Coupling

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 146(3), P. 1984 - 1991

Published: Dec. 19, 2023

Asymmetric electrocatalysis offers exciting new strategies for the synthesis of chiral molecules through novel reaction pathways. However, simultaneous activation reactants on both electrodes via asymmetric paired electrolysis, which is more energy efficient and economic than single half-electrode synthesis, remains a formidable challenge. Herein, an olefin–sulfonylimine coupling presented first time. In this protocol, Co-catalyzed hydrogen atom transfer anode Ni-catalyzed sulfonylimine reduction cathode were seamlessly cross-coupled. The catalytic system enables formation amine products bearing tetrasubstituted carbon stereocenter with high enantioselectivity (up to 96% ee).

Language: Английский

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