Electrochemical strategies for C–H functionalization and C–N bond formation

Chemical Society Reviews, Год журнала: 2018, Номер 47(15), С. 5786 - 5865

Опубликована: Янв. 1, 2018

This review provides an overview of the use electrochemistry as appealing platform for expediting carbon–hydrogen functionalization and carbon–nitrogen bond formation.

Язык: Английский

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Cross-Coupling and Related Reactions: Connecting Past Success to the Development of New Reactions for the Future

Organometallics, Год журнала: 2018, Номер 38(1), С. 3 - 35

Опубликована: Ноя. 27, 2018

Cross-coupling reactions, which were discovered almost 50 years ago, are widely used in both industry and academia. Even though cross-coupling reactions now represent mature technology, there is still a significant amount of research this area that aims to improve the scope these develop more efficient catalysts, make practical. In tutorial, brief background provided, then major advances over last 20 described. These include development improved ligands precatalysts for extension much wider range electrophiles. For example, common with sp3-hybridized electrophiles as well ester, amide, ether, aziridine substrates. many modern substrates, traditional palladium-based catalysts less than systems based on first-row transition metals such nickel. Conventional have also inspired related cross-electrophile decarboxylative couplings metallaphotoredox chemistry. The new probably at same stage 30 tutorial highlights how strategies may be applicable making

Язык: Английский

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Well-Defined Palladium(II)–NHC Precatalysts for Cross-Coupling Reactions of Amides and Esters by Selective N–C/O–C Cleavage

Accounts of Chemical Research, Год журнала: 2018, Номер 51(10), С. 2589 - 2599

Опубликована: Сен. 21, 2018

Transition-metal-catalyzed cross-coupling reactions represent a most powerful tool for the rapid construction of C-C and C-X bonds available to synthetic chemists. Recently, tremendous progress has been made in burgeoning area amides esters enabled by regio- chemoselective acyl (X = N, O) cleavage using well-defined Pd(II)-NHC complexes. The use N-heterocyclic carbenes as ligands palladium-catalyzed cross-couplings permits that were previously impossible palladium or could be achieved only under harsh conditions. These provide an attractive method chemists manipulate traditionally inert amide ester with broad generality inherent catalysis. Research stable electrophiles can broadly categorized type electrophile undergoing cross-coupling. Recent studies have shown transition-metal catalysis represents one straightforward wide-ranging ways manipulating classically into generic acyl-metal intermediates systematically exploited new paradigm organic synthesis. key achieving high chemoselectivity process is control amidic resonance (nN πC═O* conjugation, rotation ca. 15-20 kcal/mol planar amides), enabling oxidative addition N-C bond metal rational predictable manner. This mode extended C(acyl)-O aryl esters, where selective C-O accomplished through match nucleophilic catalysts. two types transition-metal-catalyzed concept chemistry because ubiquity precursors Furthermore, stability provides unprecedented opportunities orthogonal strategies presence other electrophiles. In this Account, we highlight advances taken place past few years field focusing on both (1) stereoelectronic properties complexes critical realize challenging manifold (2) role isomerization barrier broader sense, described here practical approach functionalize common functional groups synthesis establishes access enable nonconventional strategies.

Язык: Английский

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Amide activation: an emerging tool for chemoselective synthesis

Chemical Society Reviews, Год журнала: 2018, Номер 47(21), С. 7899 - 7925

Опубликована: Янв. 1, 2018

This review focusses on the use of amide activation for chemoselective functionalisation and its application in natural product synthesis.

Язык: Английский

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Single Electron Transfer-Induced Redox Processes Involving N-(Acyloxy)phthalimides

ACS Catalysis, Год журнала: 2021, Номер 11(3), С. 1640 - 1683

Опубликована: Янв. 20, 2021

The past decade has witnessed the emergence of N-(acyloxy)phthalimides (NHPI esters) and its derivatives at forefront synthetic methods facilitating construction diverse molecular frameworks from readily available carboxylic acid feedstock. NHPI esters are predisposed to undergo reductive fragmentation via a single electron transfer (SET) process under thermal, photochemical, or electrochemical conditions generate corresponding carbon- nitrogen-centered radicals that participate in multitude transformations forge carbon–carbon carbon–heteroatom bonds. chemistry involving received broad applicability not only well-designed cascade annulations but also medicinal natural product synthesis. This comprehensive Review, broadly categorized according nature bond formation, details progress made this field since initial discovery by providing representative examples with mechanistic details, an emphasis on challenges future directions.

Язык: Английский

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A general deoxygenation approach for synthesis of ketones from aromatic carboxylic acids and alkenes

Nature Communications, Год журнала: 2018, Номер 9(1)

Опубликована: Авг. 23, 2018

Abstract The construction of an aryl ketone structural unit by means catalytic carbon–carbon coupling reactions represents the state-of-the-art in organic chemistry. Herein we achieved direct deoxygenative synthesis aqueous solution from readily available aromatic carboxylic acids and alkenes, affording structurally diverse ketones moderate to good yields. Visible-light photoredox catalysis enables deoxygenation as acyl sources with triphenylphosphine a distinct perspective on activation. synthetic robustness is supported late-stage modification several pharmaceutical compounds complex molecules. This strategy further applied drug zolpidem three steps 50% total yield concise cyclophane-braced 18–20 membered macrocycloketones. It not only advancement for streamlined feedstock chemicals, but also radical activation mode beyond redox potential acids.

Язык: Английский

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First-Row d-Block Element-Catalyzed Carbon–Boron Bond Formation and Related Processes

Chemical Reviews, Год журнала: 2021, Номер 121(21), С. 13238 - 13341

Опубликована: Окт. 7, 2021

Organoboron reagents represent a unique class of compounds because their utility in modern synthetic organic chemistry, often affording unprecedented reactivity. The transformation the carbon–boron bond into carbon–X (X = C, N, and O) stereocontrolled fashion has become invaluable medicinal agrochemistry, natural products chemistry as well materials science. Over past decade, first-row d-block transition metals have increasingly widely used catalysts for formation bond, traditionally catalyzed by expensive precious metals. This recent focus on alternative enabled growth fundamental methods organoboron chemistry. review surveys current state-of-the-art use element-based bonds.

Язык: Английский

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Selective Decarbonylation via Transition-Metal-Catalyzed Carbon–Carbon Bond Cleavage

Chemical Reviews, Год журнала: 2020, Номер 121(1), С. 365 - 411

Опубликована: Июнь 16, 2020

Transition-metal-catalyzed decarbonylation via carbon–carbon bond cleavage is an essential synthetic methodology. Given the ubiquity of carbonyl compounds, selective decarbonylative process offers a distinct strategy using groups as "traceless handles". This reaction has been significantly developed in recent years many respects, including catalytic system development, mechanistic understanding, substrate scope, and application synthesis complex functional molecules. Therefore, this review aims to summarize progress on transition-metal-catalyzed process, from discovery new transformations understanding mechanisms, reveal great achievements potentials field. The contents are categorized by type chemical process. main challenges opportunities also examined with goal expanding range reactions.

Язык: Английский

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Trends in the Usage of Bidentate Phosphines as Ligands in Nickel Catalysis

Chemical Reviews, Год журнала: 2020, Номер 120(13), С. 6124 - 6196

Опубликована: Июнь 3, 2020

A critically important process in catalysis is the formation of an active catalyst from combination a metal precursor and ligand, as efficacy this reaction governs amount catalyst. This Review comprehensive overview reactions catalyzed by nickel added bidentate phosphine, focusing on steps transforming precatalyst ligand into potential effects transformation catalysis. Reactions covered include common cross-coupling reactions, such Suzuki, Heck, Kumada, Negishi couplings, addition cycloadditions, C–H functionalizations, polymerizations, hydrogenations, reductive among others. Overall, most widely used with free phosphines Ni(cod)2, which accounts for ∼50% reports surveyed, distantly followed Ni(acac)2 Ni(OAc)2, account ∼10% each. By compiling these we have calculated statistics usage each Ni(cod)2 other sources. The are simple, relatively inexpensive ligands, DPPE, DCPE, DPPP, DPPB, along others more complex backbones, DPPF Xantphos. use expensive chiral scattered, but ligands BINAP, Me-Duphos, Josiphos, related analogs.

Язык: Английский

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Decarbonylative Cross-Couplings: Nickel Catalyzed Functional Group Interconversion Strategies for the Construction of Complex Organic Molecules

Accounts of Chemical Research, Год журнала: 2018, Номер 51(5), С. 1185 - 1195

Опубликована: Апрель 13, 2018

ConspectusThe utilization of carboxylic acid esters as electrophiles in metal-catalyzed cross-coupling reactions is increasingly popular, environmentally friendly and readily available ester derivatives can be powerful alternatives to the commonly used organohalides. However, key challenges associated with use these chemicals remain addressed, including stability substrates high energy barrier their oxidative addition low-valent metal species. Due recent developments nickel catalysis that make it easier perform additions, chemists have become interested applying less reactive coupling counterparts nickel-catalyzed transformations. Hence, our group others independently investigated various substitutions functionalizations enabled by catalysis. Such methods are great interest they enable exchange groups, which directing groups C–H prior replacement.Here, we summarize efforts toward development decarbonylative esters. Achievements accomplished other this area also included. To day, a number new transformations been successfully developed, arylations, alkylations, cyanations, silylations, borylations, aminations, thioetherifications, stannylations, hydrogenolysis reactions. These proceed via pathway shown degree reactivity chemoselectivity, well several unique advantages terms substrate availability, due partners.Although mechanisms not yet fully understood, already provided some important insights. For example, Yamamoto explored stoichiometric nickel-mediated decarbonylation process proposed reaction mechanism involving C(acyl)–O bond cleavage CO extrusion. Key intermediates were isolated characterized Shi co-workers, supporting assumption nickel/N-heterocyclic carbene-promoted activation functionalization. Our combined experimental computational study ligand-controlled chemoselective aromatic alkylboron reagents further insight into mechanism.We demonstrated complexes bidentate ligands favor C(aryl)–C step, resulting while monodentate phosphorus promote bond, leading production ketone products. Although more detailed mechanistic investigations need undertaken, successful serve solid foundation for future studies.We believe type will significant value, particularly combination retrosynthetic analysis synthesis natural products biologically active molecules. Thus, presented substitution pave way applications construction complex frameworks late-stage modification functionalization derivatives.

Язык: Английский

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