Enantioselective C−H Activation with Earth‐Abundant 3d Transition Metals

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 58(37), P. 12803 - 12818

Published: May 11, 2019

Molecular syntheses largely rely on time- and labour-intensive prefunctionalization strategies. In contrast, C-H activation represents an increasingly powerful approach that avoids lengthy of prefunctionalized substrates, with great potential for drug discovery, the pharmaceutical industry, material sciences, crop protection, among others. The enantioselective functionalization omnipresent bonds has emerged as a transformative tool step- atom-economical generation chiral molecular complexity. However, this rapidly growing research area remains dominated by noble transition metals, prominently featuring toxic palladium, iridium rhodium catalysts. Indeed, despite significant achievements, use inexpensive sustainable 3d metals in asymmetric activations is still clearly its infancy. Herein, we discuss remarkable recent progress transformations via organometallic base up to April 2019.

Language: Английский

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Enantioselective Pallada‐Electrocatalyzed C−H Activation by Transient Directing Groups: Expedient Access to Helicenes

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(32), P. 13451 - 13457

Published: April 3, 2020

Abstract Asymmetric pallada‐electrocatalyzed C−H olefinations were achieved through the synergistic cooperation with transient directing groups. The electrochemical, atroposelective activations realized high position‐, diastereo‐, and enantio‐control under mild reaction conditions to obtain highly enantiomerically‐enriched biaryls fluorinated N−C axially chiral scaffolds. Our strategy provided expedient access to, among others, novel BINOLs, dicarboxylic acids helicenes of value asymmetric catalysis. Mechanistic studies by experiments computation key insights into catalyst's mode action.

Language: Английский

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Chiral Cyclopentadienyl Ligands: Design, Syntheses, and Applications in Asymmetric Catalysis

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 60(24), P. 13198 - 13224

Published: July 16, 2020

The creation of new chiral ligands capable providing high stereocontrol in metal-catalyzed reactions is crucial modern organic synthesis. production bioactive molecules as single enantiomers increasingly required, and asymmetric catalysis with metal complexes constitutes one the most efficient synthetic strategies to access optically active compounds. Herein we offer a historical overview on development derivatives ubiquitous cyclopentadienyl ligand (CpX ), detail their successful application broad range transformations. Those include functionalization challenging C-H bonds beyond, giving an extensive catalogue valuable molecules. A critical comparison existing families, design, synthesis, complexation different metals also provided. In addition, future research directions are discussed further enhance performance CpX enantioselective catalysis.

Language: Английский

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Transition Metal Catalyzed Enantioselective C(sp²)–H Bond Functionalization

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(23), P. 13748 - 13793

Published: Nov. 12, 2020

Direct catalytic transformation of C–H bonds to new functionalities has provided a powerful strategy synthesize complex molecular scaffolds in straightforward way. Unstinting efforts the synthetic community have helped overcome long-standing major challenge regioselectivity by introducing directing group concept. However, full potential cannot be realized unless activated are stereochemically controlled. The enantioselective bond functionalization could provide an imperative tool for sustainable way synthesizing chiral scaffolds. Despite intrinsic challenges achieving stereocontrol, developed different tools order achieve stereoselective functionalization. In this review, we discuss remarkable recent advances emerging area C(sp2)–H highlight and opportunities, emphasizing techniques so far.

Language: Английский

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Enantioselective C H Bond Functionalizations by 3d Transition-Metal Catalysts

Trends in Chemistry, Journal Year: 2019, Volume and Issue: 1(5), P. 471 - 484

Published: April 20, 2019

Language: Английский

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Diverse Approaches for Enantioselective C−H Functionalization Reactions Using Group 9 Cp^xM^III Catalysts

Chemistry - A European Journal, Journal Year: 2020, Volume and Issue: 26(33), P. 7346 - 7357

Published: Jan. 29, 2020

Transition-metal-catalyzed C-H functionalization reactions with Cp*MIII catalysts (M=Co, Rh, Ir) have found a wide variety of applications in organic synthesis. Albeit the intrinsic difficulties achieving catalytic stereocontrol using these due to their lack additional coordination sites for external chiral ligands and conformational flexibility Cp ligand, enantioselective Group 9 metal triad Cp-type been intensively studied since 2012. In this minireview, progress according type catalyst used are summarized discussed. The development Cpx complexes thereof, artificial metalloenzymes, carboxylate-assisted activations, alkylations assisted by carboxylic acids or sulfonates, transient directing groups

Language: Английский

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Enantioselective electrochemical cobalt-catalyzed aryl C–H activation reactions

Science, Journal Year: 2023, Volume and Issue: 379(6636), P. 1036 - 1042

Published: March 10, 2023

Enantioselective redox transformations typically rely on costly transition metals as catalysts and often stoichiometric amounts of chemical agents well. Electrocatalysis represents a more sustainable alternative, in particular through the use hydrogen evolution reaction (HER) place oxidant. In this work, we describe strategies for HER-coupled enantioselective aryl carbon-hydrogen bond (C-H) activation reactions using cobalt precious metal catalyst asymmetric oxidation. Thus, highly nitrogen-hydrogen (C-H N-H) annulations carboxylic amides were achieved, which gave access to point axially chiral compounds. Furthermore, cobalt-mediated electrocatalysis enabled preparation various phosphorus (P)-stereogenic compounds by selective desymmetrization dehydrogenative C-H reactions.

Language: Английский

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Generation of Heteroatom Stereocenters by Enantioselective C–H Functionalization

ACS Catalysis, Journal Year: 2019, Volume and Issue: 9(10), P. 9164 - 9177

Published: Aug. 30, 2019

C–H functionalization has been established as an efficient way to generate molecular complexity. The formation of stereogenic carbon atoms by asymmetric seen tremendous progress over the past decade. More recently, direct catalytic modification bonds powerfully applied noncarbon centers, which constitute a key design element biologically active molecules and chiral ligands for catalysis. This area was opened seminal report describing enantioselective silicon stereocenter. It rapidly expanded with advances in phosphorus(V) centers. Moreover, routes sulfur oxidation states IV (sulfoxides) VI (sulfoximines) have disclosed. Herein, we discuss methods using selective remote heteroatom center via inner-sphere activation mechanism.

Language: Английский

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Divergent Synthesis of Tunable Cyclopentadienyl Ligands and Their Application in Rh-Catalyzed Enantioselective Synthesis of Isoindolinone

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(16), P. 7379 - 7385

Published: April 7, 2020

A series of rhodium complexes bearing sterically and electronically tunable cyclopentadienyl ligands, prepared by utilizing Co2(CO)8-mediated [2+2+1] cyclization as a key step, were synthesized. In the presence 2.5 mol% CpmRh4, unprecedented enantioselective [4+1] annulation reaction benzamides alkenes was achieved with broad substrate scope under mild conditions, providing variety isoindolinones excellent regio- enantioselectivity (up to 94% yield, 97:3 er). Preliminary mechanistic studies suggest that involves an oxidative Heck intramolecular alkene hydroamination reaction.

Language: Английский

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Weak-Coordination in C–H Bond Functionalizations Catalyzed by 3d Metals

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(6), P. 3452 - 3506

Published: March 3, 2022

Transition-metal-catalyzed C–H bond functionalizations have had an enormous influence on organic synthesis in recent times. However, the use of low-abundance 4d and 5d metals is almost inevitable, they are high demand. This will be a cause concern, hence, it important to develop methods based 3d metals, which widely present Earth's crust. In this regard, metal catalysts or their precursors for catalysis, general, functionalizations, particular, has gained significant momentum The major development catalytic with been achieved predominantly strongly coordinating directing groups such as pyridyl, pyrimidinyl, pyrazolyl, 8-amino-quinolinyl groups. Thus, prefunctionalization substrates these necessary, contradicts step- atom-economy activation. commonly available functional aldehyde, ketone, carboxylic acid, amide, hydroxy, N-oxides loosely bind through weak-coordination. These weakly orient activate regioselectively without need preinstalled Although challenging, contemporary topic actively pursued by many researchers Through article, we provide comprehensive overview metal-catalyzed, coordinating, directing-group-enabled reported until March 2021.

Language: Английский

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