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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The medicinal chemist's toolbox for late stage functionalization of drug-like molecules

Chemical Society Reviews, Год журнала: 2015, Номер 45(3), С. 546 - 576

Опубликована: Окт. 28, 2015

The advent of modern C-H functionalization chemistries has enabled medicinal chemists to consider a synthetic strategy, late stage (LSF), which utilizes the bonds drug leads as points diversification for generating new analogs. LSF approaches offer promise rapid exploration structure activity relationships (SAR), generation oxidized metabolites, blocking metabolic hot spots and preparation biological probes. This review details toolbox intermolecular with proven applicability drug-like molecules, classified by regioselectivity patterns, gives guidance on how systematically develop strategies using these patterns other considerations. In addition, number examples illustrate have been used impact actual discovery chemical biology efforts.

Язык: Английский

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Cobalt-Catalyzed C–H Activation

ACS Catalysis, Год журнала: 2015, Номер 6(2), С. 498 - 525

Опубликована: Ноя. 24, 2015

Catalytic C–H activation has emerged as a powerful tool for sustainable syntheses. In the recent years, notable success was achieved with development of cobalt-catalyzed functionalizations either in situ generated or single-component cobalt-complexes under mild reaction conditions. Herein, progress field organometallic is reviewed until November 2015.

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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Direct Photocatalyzed Hydrogen Atom Transfer (HAT) for Aliphatic C–H Bonds Elaboration

Chemical Reviews, Год журнала: 2021, Номер 122(2), С. 1875 - 1924

Опубликована: Авг. 6, 2021

Direct photocatalyzed hydrogen atom transfer (d-HAT) can be considered a method of choice for the elaboration aliphatic C–H bonds. In this manifold, photocatalyst (PCHAT) exploits energy photon to trigger homolytic cleavage such bonds in organic compounds. Selective bond may achieved by judicious abstractor (key parameters are electronic character and molecular structure), as well reaction additives. Different classes PCsHAT available, including aromatic ketones, xanthene dyes (Eosin Y), polyoxometalates, uranyl salts, metal-oxo porphyrin tris(amino)cyclopropenium radical dication. The processes (mainly C–C formation) most cases carried out under mild conditions with help visible light. aim review is offer comprehensive survey synthetic applications d-HAT.

Язык: Английский

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Formal S_N‐Type Reactions in Rhodium(III)‐Catalyzed CH Bond Activation

Advanced Synthesis & Catalysis, Год журнала: 2014, Номер 356(7), С. 1443 - 1460

Опубликована: Май 5, 2014

Abstract (Pentamethylcyclopentadienyl)rhodium (RhCp*)‐catalyzed CH transformations have emerged as a prosperous field in bond activation. Recent advances this area significantly focused on the development of new strategies for CC and Cheteroatom formation that are characterized by novel reactivity RhCp* catalyst to undergo formal S N ‐type reactions with electrophilic substrates. This review is intended give an overview rather class RhCp*‐catalyzed transformations, covering recent bond‐forming reactions. The nature reaction partner these functionalization serves guideline throughout article and, combined selected descriptions mechanistic proposals, should emphasize general characteristics within class. magnified image

Язык: Английский

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Oxidative C–H amination reactions

Chemical Society Reviews, Год журнала: 2013, Номер 43(3), С. 901 - 910

Опубликована: Ноя. 11, 2013

Towards "Oxidative-Ullmann-Goldberg" and "Oxidative-Buchwald-Hartwig" type amination reactions. This review focuses on the newly developed oxidative C-N bond formation techniques, applicable in field of organic synthesis. Particular emphasis is given to those which are classified as cross-dehydrogenative-couplings, through dual C-H N-H activation, thus formally extruding "H2" a by-product.

Язык: Английский

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Undirected, Homogeneous C–H Bond Functionalization: Challenges and Opportunities

ACS Central Science, Год журнала: 2016, Номер 2(5), С. 281 - 292

Опубликована: Май 2, 2016

The functionalization of C–H bonds has created new approaches to preparing organic molecules by enabling strategic "disconnections" during the planning a synthetic route. Such functionalizations also have ability derivatize complex modifying one or more many bonds. For these reasons, researchers are developing types reactions and applications processes. These bond can be divided into two general classes: those directed coordination an existing functional group prior cleavage (directed) occurring without (undirected). undirected much less common challenging develop than reactions. This outlook will focus on functionalization, as well related that occur noncovalent association catalyst cleavage. inherent challenges conducting methods for being developed presented, along with factors govern selectivity in Finally, this discusses future directions research emphasis limitations must overcome if type methodology is become widely used academia industry.

Язык: Английский

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Evolution of C–H Bond Functionalization from Methane to Methodology

Journal of the American Chemical Society, Год журнала: 2015, Номер 138(1), С. 2 - 24

Опубликована: Ноя. 13, 2015

This Perspective presents the fundamental principles, elementary reactions, initial catalytic systems, and contemporary catalysts that have converted C–H bond functionalization from a curiosity to reality for synthetic chemists. Many classes of reactions involving transition-metal complexes cleave bonds at typically unreactive positions. These coupled with separate or simultaneous process lead products containing new C–C, C–N, C–O bonds. Such were initially studied conversion light alkanes liquid products, but they been used (and commercialized in some cases) most often synthesis more complex structures natural medicinally active compounds, aromatic materials. change direction research is remarkable because must occur an unactivated over functional groups are reactive than toward classical reagents. The scope form C–C install functionality will be presented, potential future utility these discussed.

Язык: Английский

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Photoredox Catalysis for Building C–C Bonds from C(sp²)–H Bonds

Chemical Reviews, Год журнала: 2018, Номер 118(16), С. 7532 - 7585

Опубликована: Июль 16, 2018

Transition metal-catalyzed C–H bond functionalizations have been the focus of intensive research over last decades for formation C–C bonds from unfunctionalized arenes, heteroarenes, alkenes. These direct transformations provide new approaches in synthesis with high atom- and step-economy compared to traditional catalytic cross-coupling reactions. However, such methods still suffer several limitations including functional group tolerance lack regioselectivity. In addition, they often require harsh reaction conditions some them need use strong oxidant, a stoichiometric amount, avoiding these processes be truly eco-friendly. The photoredox catalysis has contributed significant expansion scope C(sp2)–H which include arylations, (perfluoro)alkylations, acylations, even cyanations. Most involve photochemical induced generation radical followed by its regioselective addition or alkenes, leading building C(sp2)–C bond. plays crucial roles reactions promoting electron transfer, enabling species single either oxidation reduction. Such operating at room temperature allow chemo-, regio-, stereoselectivity. This review surveys initiated involves functionalization step, describes advantages functionalizations, presents mechanistic insights into role played catalysts.

Язык: Английский

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