Radical Carboxylative Cyclizations and Carboxylations with CO₂

Accounts of Chemical Research, Journal Year: 2021, Volume and Issue: 54(10), P. 2518 - 2531

Published: May 6, 2021

ConspectusCarbon dioxide (CO2) is not only a greenhouse gas and common waste product but also an inexpensive, readily available, renewable carbon resource. It important one-carbon (C1) building block in organic synthesis for the construction of valuable compounds. However, its utilization challenging owing to thermodynamic stability kinetic inertness. Although significant progress has been achieved, many limitations remain this field with regard substrate scope, reaction system, activation strategies.Since 2015, our group focused on CO2 synthesis. We are interested vast possibilities radical chemistry, although high reactivity radicals presents challenges controlling selectivity. hope develop highly useful transformations involving by achieving balance selectivity under mild conditions. Over past 6 years, we along other experts have disclosed radical-type carboxylative cyclizations carboxylations using CO2.We initiated research realizing Cu-catalyzed oxytrifluoromethylation allylamines heteroaryl methylamines generate 2-oxazolidones various precursors. Apart from Cu catalysis, visible-light photoredox catalysis powerful method achieve efficient cyclization. In these cases, single-electron-oxidation-promoted C–O bond formation between benzylic carbamates key step.Since carboxylic acids exist widely natural products bioactive drugs serve as bulk chemicals industry, realized further visible-light-promoted construct such chemicals. achieved selective umpolung imines, enamides, tetraalkylammonium salts, oxime esters successive single-electron-transfer (SSET) reduction. Using strategy, dearomative arylcarboxylation indoles CO2. addition incorporation 1 equiv per substrate, recently developed photoredox-catalyzed dicarboxylation alkenes, allenes, (hetero)arenes via SSET reduction, which allows two molecules into compounds diacids polymer precursors.In two-electron CO2, sought new strategies realize single-electron Inspired hypothetical electron-transfer mechanism iron–sulfur proteins, visible-light-driven thiocarboxylation alkenes catalytic iron salts promoters. The in-situ-generated Fe/S complexes likely able reduce anion, could react give stabilized radical. Moreover, charge-transfer complex (CTC) thiolate acrylate/styrene hydrocarboxylation generation or alkene anion. On basis novel CTC, organocatalytic Hantzsch ester effective reductant.

Language: Английский

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Acridinium Salts and Cyanoarenes as Powerful Photocatalysts: Opportunities in Organic Synthesis

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(36), P. 19526 - 19549

Published: April 22, 2021

The use of organic photocatalysts has revolutionized the field photoredox catalysis, as it allows access to reactivities that were traditionally restricted transition-metal photocatalysts. This Minireview reports recent developments in acridinium ions and cyanoarene derivatives synthesis. activation inert chemical bonds well late-stage functionalization biorelevant molecules are discussed, with a special focus on their mechanistic aspects.

Language: Английский

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Visible-light photocatalytic di- and hydro-carboxylation of unactivated alkenes with CO2

Nature Catalysis, Journal Year: 2022, Volume and Issue: 5(9), P. 832 - 838

Published: Sept. 15, 2022

Language: Английский

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Electrochemical Ring-Opening Dicarboxylation of Strained Carbon–Carbon Single Bonds with CO₂: Facile Synthesis of Diacids and Derivatization into Polyesters

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(5), P. 2062 - 2068

Published: Jan. 27, 2022

Diacids are important monomers in the polymer industry to construct valuable materials. Dicarboxylation of unsaturated bonds, such as alkenes and alkynes, with CO2 has been demonstrated a promising synthetic method. However, dicarboxylation C─C single bonds rarely investigated. Herein we report novel electrochemical ring-opening strained rings CO2. Structurally diverse glutaric acid adipic derivatives were synthesized from substituted cyclopropanes cyclobutanes moderate high yields. In contrast oxidative ring openings, this is also first realization an electroreductive reaction rings, including commercialized ones. Control experiments suggested that radical anions carbanions might be key intermediates reaction. Moreover, process features step atom economy, mild conditions (1 atm, room temperature), good chemoselectivity functional group tolerance, low electrolyte concentration, easy derivatization products. Furthermore, conducted polymerization corresponding diesters diols obtain potential UV-shielding material self-healing function fluorine-containing polyester, whose performance tests showed applications.

Language: Английский

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Electrochemical Dearomative Dicarboxylation of Heterocycles with Highly Negative Reduction Potentials

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(8), P. 3685 - 3695

Published: Feb. 22, 2022

The dearomative dicarboxylation of stable heteroaromatics using CO2 is highly challenging but represents a very powerful method for producing synthetically useful dicarboxylic acids, which can potentially be employed as intermediates biologically active molecules such natural products and drug leads. However, these types transformations are still underdeveloped, concise methodologies with high efficiency (e.g., yield selectivity dicarboxylations) have not been reported. We herein describe new electrochemical protocol the radical anion (E1/2 = -2.2 V in DMF -2.3 CH3CN vs SCE) that produces unprecedented trans-oriented 2,3-dicarboxylic acids from N-Ac-, Boc-, Ph-protected indoles exhibit negative reduction potentials (-2.50 to -2.94 V). On basis calculated potentials, N-protected up -3 smoothly undergo desired dicarboxylation. Other heteroaromatics, including benzofuran, benzothiophene, electron-deficient furans, thiophenes, 1,3-diphenylisobenzofuran, N-Boc-pyrazole, also more positive than served effective substrates dicarboxylations. dicarboxylated thus obtained derivatized into synthetic compounds few steps. show how monocarboxylation achieved selectively by choice electrolyte, solvent, protic additive; this strategy was then applied synthesis an octahydroindole-2-carboxylic acid (Oic) derivative, proline analogue.

Language: Английский

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Boryl Radical Activation of Benzylic C–OH Bond: Cross-Electrophile Coupling of Free Alcohols and CO₂ via Photoredox Catalysis

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(19), P. 8551 - 8559

Published: April 4, 2022

A new strategy for the direct cleavage of C(sp3)-OH bond has been developed via activation free alcohols with neutral diphenyl boryl radical generated from sodium tetraphenylborate under mild visible light photoredox conditions. This verified by cross-electrophile coupling and carbon dioxide synthesis carboxylic acids. Direct transformation a range primary, secondary, tertiary benzyl to acids achieved. Control experiments computational studies indicate that undergoes homolysis bond, generating alkyl radicals. After reducing into anion conditions, following carboxylation CO2 affords product.

Language: Английский

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Recent Advances in Electrocarboxylation with CO₂

Chemistry - An Asian Journal, Journal Year: 2022, Volume and Issue: 17(17)

Published: July 6, 2022

Abstract Carbon dioxide (CO 2 ) is an abundant, inexpensive, renewable C1 resource and the main component of greenhouse gas, thereby research for its sustainable efficient conversion has received notable attention in recent years. Electrochemical organic synthesis, as a green synthetic method, convinced to be ideal approach CO utilization. In this review, advances electrocarboxylation with were summarized through different reaction types, which would disclose great potential synthesis.

Language: Английский

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Recent progress in CO₂ conversion into organic chemicals by molecular catalysis

Green Chemistry, Journal Year: 2023, Volume and Issue: 25(17), P. 6538 - 6560

Published: Jan. 1, 2023

An activation toolbox for the effective catalytic conversion of CO 2 to chemicals is proposed along with challenges and prospects related future development this exciting technology.

Language: Английский

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Dicarboxylation of Alkenes with CO₂ and Formate via Photoredox Catalysis

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(3), P. 2149 - 2155

Published: Jan. 25, 2023

Herein, a photocatalytic strategy for the synthesis of succinic acids by alkene dicarboxylation with carbon dioxide (CO2) and formate salt as synergistic sources is described. The acts both C1 source reductant in reaction catalytic amount 1,4-diazabicyclo[2.2.2]octane (DABCO) hydrogen atom transfer reagent. Various mono-, di-, trisubstituted alkenes, acrylate, acrylamide, indole derivatives could be converted to corresponding diacids, which provided potential useful applications medicinal chemistry polymer industry.

Language: Английский

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Electroreductive Dicarboxylation of Unactivated Skipped Dienes with CO₂

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(23)

Published: April 3, 2023

Carboxylation of easily available alkenes with CO2 is highly important to afford value-added carboxylic acids. Although dicarboxylation activated alkenes, especially 1,3-dienes, has been widely investigated, the challenging unactivated 1,n-dienes (n>3) remains unexplored. Herein, we report first skipped dienes via electrochemistry, affording valuable dicarboxylic Control experiments and DFT calculations support single electron transfer (SET) reduction its radical anion, which followed by sluggish addition SET unstabilized alkyl radicals carbanions nucleophilic attack on give desired products. This reaction features mild conditions, broad substrate scope, facile derivations products promising application in polymer chemistry.

Language: Английский

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