3d Transition Metals for C–H Activation

Chemical Reviews, Год журнала: 2018, Номер 119(4), С. 2192 - 2452

Опубликована: Ноя. 27, 2018

C–H activation has surfaced as an increasingly powerful tool for molecular sciences, with notable applications to material crop protection, drug discovery, and pharmaceutical industries, among others. Despite major advances, the vast majority of these functionalizations required precious 4d or 5d transition metal catalysts. Given cost-effective sustainable nature earth-abundant first row metals, development less toxic, inexpensive 3d catalysts gained considerable recent momentum a significantly more environmentally-benign economically-attractive alternative. Herein, we provide comprehensive overview on until summer 2018.

Язык: Английский

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Transition Metal-Catalyzed C–H Amination: Scope, Mechanism, and Applications

Chemical Reviews, Год журнала: 2017, Номер 117(13), С. 9247 - 9301

Опубликована: Янв. 4, 2017

Catalytic transformation of ubiquitous C-H bonds into valuable C-N offers an efficient synthetic approach to construct N-functionalized molecules. Over the last few decades, transition metal catalysis has been repeatedly proven be a powerful tool for direct conversion cheap hydrocarbons synthetically versatile amino-containing compounds. This Review comprehensively highlights recent advances in intra- and intermolecular amination reactions utilizing late metal-based catalysts. Initial discovery, mechanistic study, additional applications were categorized on basis scaffolds types reactions. Reactivity selectivity novel systems are discussed three sections, with each being defined by proposed working mode.

Язык: Английский

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Palladium-Catalyzed Transformations of Alkyl C–H Bonds

Chemical Reviews, Год журнала: 2016, Номер 117(13), С. 8754 - 8786

Опубликована: Дек. 2, 2016

This Review summarizes the advancements in Pd-catalyzed C(sp3)-H activation via various redox manifolds, including Pd(0)/Pd(II), Pd(II)/Pd(IV), and Pd(II)/Pd(0). While few examples have been reported of alkane C-H bonds, many activation/C-C C-heteroatom bond forming reactions developed by use directing group strategies to control regioselectivity build structural patterns for synthetic chemistry. A number mono- bidentate ligands also proven be effective accelerating directed weakly coordinating auxiliaries, which provides great opportunities reactivity selectivity (including enantioselectivity) functionalization reactions.

Язык: Английский

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Mild metal-catalyzed C–H activation: examples and concepts

Chemical Society Reviews, Год журнала: 2016, Номер 45(10), С. 2900 - 2936

Опубликована: Янв. 1, 2016

C–H Activation reactions that proceed under mild conditions are more attractive for applications in complex molecule synthesis. Mild transformations reported since 2011 reviewed and the different concepts strategies have enabled their mildness discussed.

Язык: Английский

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A comprehensive overview of directing groups applied in metal-catalysed C–H functionalisation chemistry

Chemical Society Reviews, Год журнала: 2018, Номер 47(17), С. 6603 - 6743

Опубликована: Янв. 1, 2018

The present review is devoted to summarizing the recent advances (2015-2017) in field of metal-catalysed group-directed C-H functionalisation. In order clearly showcase molecular diversity that can now be accessed by means directed functionalisation, whole organized following directing groups installed on a substrate. Its aim comprehensive reference work, where specific group easily found, together with transformations which have been carried out it. Hence, primary format this schemes accompanied concise explanatory text, are ordered sections according their chemical structure. feature typical substrates used, products obtained as well required reaction conditions. Importantly, each example commented respect most important positive features and drawbacks, aspects such selectivity, substrate scope, conditions, removal, greenness. targeted readership both experts functionalisation chemistry (to provide overview progress made last years) and, even more so, all organic chemists who want introduce way thinking for design straightforward, efficient step-economic synthetic routes towards molecules interest them. Accordingly, should particular also scientists from industrial R&D sector. overall goal promote application reactions outside research dedicated method development establishing it valuable archetype contemporary R&D, comparable role cross-coupling play date.

Язык: Английский

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Iron-Catalyzed C–H Bond Activation

Chemical Reviews, Год журнала: 2017, Номер 117(13), С. 9086 - 9139

Опубликована: Апрель 5, 2017

Catalytic C-H bond activation, which was an elusive subject of chemical research until the 1990s, has now become a standard synthetic method for formation new C-C and C-heteroatom bonds. The potential activation first described ruthenium catalysis is widely exploited by use various precious metals. Driven increasing interest in utilization ubiquitous metals that are abundant nontoxic, iron rapidly growing area research, iron-catalyzed been most actively explored recent years. In this review, we summarize development stoichiometric long history, catalytic functionalization, emerged about 10 years ago. We focus review on reactions take place via reactive organoiron intermediates, excluded those as Lewis acid or radical initiator. contents categorized type cleaved formed thereafter, it covers simple substrates possessing directing group anchors catalyst to substrate, providing overview iron-mediated reported literature October 2016.

Язык: Английский

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Bidentate Directing Groups: An Efficient Tool in C–H Bond Functionalization Chemistry for the Expedient Construction of C–C Bonds

Chemical Reviews, Год журнала: 2020, Номер 120(3), С. 1788 - 1887

Опубликована: Янв. 6, 2020

During the past decades, synthetic organic chemistry discovered that directing group assisted C–H activation is a key tool for expedient and siteselective construction of C–C bonds. Among various strategies, bidentate groups are now recognized as one most efficient devices selective functionalization certain positions due to fact its metal center permits fine, tunable, reversible coordination. The family permit types assistance be achieved, such N,N-dentate, N,O-dentate, N,S-dentate auxiliaries, which categorized based on coordination site. In this review, we broadly discuss bond reactions formation bonds with aid groups.

Язык: Английский

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Palladium(II)-Catalyzed Oxidative Difunctionalization of Alkenes: Bond Forming at a High-Valent Palladium Center

Accounts of Chemical Research, Год журнала: 2016, Номер 49(11), С. 2413 - 2423

Опубликована: Окт. 14, 2016

ConspectusDifunctionalization of alkenes to incorporate two functional groups across a double bond has emerged as powerful transformation greatly increase molecular complexity in organic synthesis with improved efficiency. Historically, palladium-catalyzed difunctionalization suffered from difficulties introducing second group through reductive elimination Pd(II) intermediate and competing β-hydride reactions. To overcome these challenges, one strategy involves utilizing steric bulky ligand promote the steps center impeding reactions, which are beyond scope this Account. Alternatively, strong oxidants have been utilized generate high-valent palladium species, prone undergo form C–X bond. This new extensively applied explore enriched diversity over past decade.In Account, we discuss our exploration application "high-valent strategy" for fluorine-containing molecules that typically inaccessible other methods. These studies were focused on was initiated by nucleopalladation alkyl C–Pd(II) species high exo/endo regioselectivity. In presence nucleophilic reagents (e.g., AgF, TMSCF3, AgOCF3) (hypervalent iodine electrophilic fluorinating reagents), situ generated Pd(IV) intermediates provide corresponding C–F, C–CF3, C–OCF3 bonds. Using methods, synthesized variety heterocycles containing fluorine, trifluoromethyl, trifluoromethoxyl moieties alkene substrates under mild reaction conditions. Besides hypervalent reagents, demonstrated hydrogen peroxide, is an environmentally friendly oxidant, can oxidize C–Pd intermediates, based observation, several catalytic difunctionalizations alkenes, such aminochlorination, aminoacetoxylation, aminohydroxylation successfully developed. addition, water only waste derived oxidant. All attractive methods stereoselective introduction C–N C–O bonds via intermediates. gain deeper understanding strategy", systematic mechanistic performed illustrate stereochemistry aminopalladation elimination. results summarized final section serve guide further novel well areas, Pd-catalyzed C–H functionalization

Язык: Английский

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Electrocatalytic C–H Activation

ACS Catalysis, Год журнала: 2018, Номер 8(8), С. 7086 - 7103

Опубликована: Июнь 18, 2018

C–H activation has emerged as a transformative tool in molecular synthesis, but until recently oxidative activations have largely involved the use of stoichiometric amounts expensive and toxic metal oxidants, compromising overall sustainable nature chemistry. In sharp contrast, electrochemical been identified more efficient strategy that exploits storable electricity place byproduct-generating chemical reagents. Thus, transition-metal catalysts were shown to enable versatile reactions manner. While palladium catalysis set stage for C(sp2)–H C(sp3)–H functionalizations by N-containing directing groups, rhodium ruthenium allowed weakly coordinating amides acids. contrast these precious 4d transition metals, recent year witnessed emergence cobalt oxygenations, nitrogenations, C–C-forming [4+2] alkyne annulations. Thereby, silver(I) oxidants was prevented, improving environmentally benign catalysis. Herein, we summarize major advances organometallic otherwise inert bonds electrocatalysis through May 2018.

Язык: Английский

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Manganese-Catalyzed C–H Activation

ACS Catalysis, Год журнала: 2016, Номер 6(6), С. 3743 - 3752

Опубликована: Апрель 27, 2016

Manganese is found in the active center of numerous enzymes that operate by an outer-sphere homolytic C–H cleavage. Thus, a plethora bioinspired radical-based functionalizations manganese catalysis have been devised during past decades. In contrast, organometallic activation means has emerged only recently as increasingly viable tool organic synthesis. These manganese(I)-catalyzed processes enabled variety with ample scope, which very set stage for substitutive functionalizations. The versatile largely operates isohypsic, thus redox-neutral, mode action through chelation assistance, and provided step-economical access to structurally divers compounds relevance inter alia bioorganic, agrochemical, medicinal chemistry well material sciences.

Язык: Английский

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