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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Rhodium‐Catalyzed C(sp²)‐ or C(sp³)−H Bond Functionalization Assisted by Removable Directing Groups

Angewandte Chemie International Edition, Год журнала: 2018, Номер 58(25), С. 8304 - 8329

Опубликована: Окт. 12, 2018

Abstract In recent years, transition‐metal‐catalyzed C−H activation has become a key strategy in the field of organic synthesis. Rhodium complexes are widely used as catalysts variety functionalization reactions because their high reactivity and selectivity. The availability number rhodium various oxidation states enables diverse reaction patterns to be obtained. Regioselectivity, an important issue chemistry, can accomplished by using directing group assist reaction. However, obtain target functionalized compounds, it is also necessary use that easily removed. A wide range directed catalyzed have been reported date. this Review, we discuss Rh‐catalyzed aided removable such phenol, amine, aldehyde, ketones, ester, acid, sulfonic N‐heteroaromatic derivatives.

Язык: Английский

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Organic synthesis with the most abundant transition metal–iron: from rust to multitasking catalysts

Chemical Society Reviews, Год журнала: 2021, Номер 50(1), С. 243 - 472

Опубликована: Янв. 1, 2021

The promising aspects of iron in synthetic chemistry are being explored for three-four decades as a green and eco-friendly alternative to late transition metals. This present review unveils these rich iron-chemistry towards different transformations.

Язык: Английский

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Rh(III)-Catalyzed Asymmetric Synthesis of Axially Chiral Biindolyls by Merging C–H Activation and Nucleophilic Cyclization

Journal of the American Chemical Society, Год журнала: 2019, Номер 141(24), С. 9527 - 9532

Опубликована: Июнь 4, 2019

Enantiomeric access to pentatomic biaryls is challenging due their relatively low rotational barrier. Reported herein the mild and highly enantioselective synthesis of 2,3′-biindolyls via underexplored integration C–H activation alkyne cyclization using a unified chiral Rh(III) catalyst. The reaction proceeded initial followed by cyclization. A rhodacyclic intermediate has been isolated from stoichiometric activation, which offers direct mechanistic insight.

Язык: Английский

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Enantioselective C(sp³)–H Amidation of Thioamides Catalyzed by a Cobalt^III/Chiral Carboxylic Acid Hybrid System

Angewandte Chemie International Edition, Год журнала: 2018, Номер 58(4), С. 1153 - 1157

Опубликована: Ноя. 27, 2018

Abstract Recent advances in Cp x M III catalysis (M=Co, Rh, Ir) have enabled a variety of enantioselective C(sp 2 )−H functionalization reactions, but 3 is still largely unexplored. We describe an asymmetric amidation thioamides using achiral Co /chiral carboxylic acid hybrid catalytic system, which provides easy and straightforward access to chiral β‐amino thiocarbonyl carbonyl building blocks with quaternary carbon stereocenter.

Язык: Английский

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

Angewandte Chemie International Edition, Год журнала: 2020, Номер 60(24), С. 13198 - 13224

Опубликована: Июль 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.

Язык: Английский

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

Chemistry - A European Journal, Год журнала: 2020, Номер 26(33), С. 7346 - 7357

Опубликована: Янв. 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

Язык: Английский

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Electrooxidative Rhodium‐Catalyzed C−H/C−H Activation: Electricity as Oxidant for Cross‐Dehydrogenative Alkenylation

Angewandte Chemie International Edition, Год журнала: 2018, Номер 57(20), С. 5828 - 5832

Опубликована: Апрель 10, 2018

Abstract Rhodium(III) catalysis has enabled a plethora of oxidative C−H functionalizations, which predominantly employ stoichiometric amounts toxic and/or expensive metal oxidants. In contrast, we herein describe the first electrochemical rhodium‐catalyzed activation that avoids hazardous chemical Environmentally benign twofold C−H/C−H functionalizations were accomplished with weakly coordinating benzoic acids and benzamides, employing electricity as terminal oxidant generating H 2 sole byproduct.

Язык: Английский

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Ir-Catalyzed Intermolecular Branch-Selective Allylic C–H Amidation of Unactivated Terminal Olefins

Journal of the American Chemical Society, Год журнала: 2019, Номер 141(6), С. 2268 - 2273

Опубликована: Фев. 4, 2019

An efficient method for intermolecular branch-selective allylic C–H amidation has been accomplished via Ir(III) catalysis. The reaction proceeds through initial activation, supported by the isolation and crystallographic characterization of an allyl-Ir(III) intermediate, followed a subsequent oxidative with readily available dioxazolones as nitrenoid precursors. A diverse range amides are successfully installed at branched position terminal alkenes in good yields regioselectivities. Importantly, allows use amide-derived precursors avoiding problematic Curtius-type rearrangements.

Язык: Английский

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Cp*Co(III)/MPAA-Catalyzed Enantioselective Amidation of Ferrocenes Directed by Thioamides under Mild Conditions

Organic Letters, Год журнала: 2019, Номер 21(6), С. 1895 - 1899

Опубликована: Март 6, 2019

Cp*Cobalt(III)-catalyzed enantioselective C-H amidation of ferrocenes using monoprotected amino acids (MPAAs) as chiral ligands was developed. The reaction performed under mild conditions in high yields (up to 97%) with moderate enantioselectivity 77.5:22.5 er), providing a promising strategy create planar chirality via base-metal-catalyzed activation.

Язык: Английский

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