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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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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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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Chiral Cyclopentadienyl Cobalt(III) Complexes Enable Highly Enantioselective 3d-Metal-Catalyzed C–H Functionalizations

Journal of the American Chemical Society, Год журнала: 2019, Номер 141(14), С. 5675 - 5680

Опубликована: Март 22, 2019

The synthesis of a set cobalt(III)-complexes equipped with trisubstituted chiral cyclopentadienyl ligands is reported, and their steric electronic parameters are mapped. application potential these complexes for asymmetric C-H functionalizations 3d-metals shown by the dihydroisoquinolones from N-chlorobenzamides broad range alkenes. transformation proceeds excellent enantioselectivities up to 99.5:0.5 er high regioselectivities. observed values outperform best rhodium(III)-based methods this reaction type. Moreover, challenging substrates such as alkyl alkenes also react regio- enantioselectivities.

Язык: Английский

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Iron- and cobalt-catalyzed C(sp³)–H bond functionalization reactions and their application in organic synthesis

Chemical Society Reviews, Год журнала: 2020, Номер 49(15), С. 5310 - 5358

Опубликована: Янв. 1, 2020

This review highlights the developments in iron and cobalt catalyzed C(sp³)–H bond functionalization reactions with emphasis on their applications organic synthesis, i.e. natural products pharmaceuticals synthesis and/or modification.

Язык: Английский

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Cobalt-Catalyzed Enantioselective C–H Annulation with Alkenes

ACS Catalysis, Год журнала: 2023, Номер 13(7), С. 4250 - 4260

Опубликована: Март 13, 2023

Herein, we disclose an efficient cobalt-catalyzed enantioselective C–H activation and annulation of benzamides with alkenes. This transformation is facilitated via the commercially available cobalt(II) catalyst in presence easily prepared chiral salicyl-oxazoline (Salox) ligand, which provides facile access to (R) or (S) enantiomers dihydroisoquinolone derivatives. It noticeable that reaction proceeded efficiently within extremely short time from 10 30 min under mild conditions. A broad range alkenes bear various functional substituents have been shown good compatibility deliver targeted products high yields enantioselectivities (51 examples, up 98% yield 99% ee). The gram scale experiment removal directing group further demonstrate practicability this protocol potential industrial applications. Density theory calculations elucidate mechanism, spin-state change olefin insertion step accelerates subsequent C–N reductive elimination, identified as stereo-determining step. AIM analysis indicates π interactions are vital for controlling switching stereoselectivity.

Язык: Английский

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Enantiodivergent Desymmetrization in the Rhodium(III)‐Catalyzed Annulation of Sulfoximines with Diazo Compounds

Angewandte Chemie International Edition, Год журнала: 2018, Номер 57(47), С. 15534 - 15538

Опубликована: Окт. 11, 2018

RhIII - and IrIII -catalyzed asymmetric C-H functionalization reactions of arenes have relied on the employment chiral /IrIII cyclopentadienyl catalysts, introduction carboxylic acids to achiral Cp*RhX2 integration both strategies. Despite considerable progress, each reaction only provided a specific configuration enantioenriched product when using particular catalyst. Reported in this work is enantiodivergent coupling sulfoximines with various diazo compounds by desymmetrizing annulation. The enantiodivergence was enabled judicious choice acids, enantioselectivity correlates steric bias acid sulfoximine.

Язык: Английский

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Cobalt‐Catalyzed Annulation Reactions via C−H Bond Activation

ChemCatChem, Год журнала: 2017, Номер 10(4), С. 683 - 705

Опубликована: Ноя. 1, 2017

Abstract Considerable research attention has been directed towards the use of first‐row transition metals in organic synthesis. The more abundant, and less expensive cobalt is considered to be an effective alternative for second third‐row noble metals, especially C−H bond functionalization reactions. In this Minireview, we will summarize features, recent achievements Co‐catalyzed directing group assisted activation/cyclization reactions their mechanistic insights.

Язык: Английский

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Thioamide‐Directed Cobalt(III)‐Catalyzed Selective Amidation of C(sp³)−H Bonds

Angewandte Chemie International Edition, Год журнала: 2017, Номер 56(52), С. 16550 - 16554

Опубликована: Окт. 28, 2017

A mild, oxidant-free, and selective Cp*CoIII -catalyzed amidation of thioamides with robust dioxazolone amidating agents via C(sp3 )-H bond activation to generate the desired amidated products is reported. The method efficient allows for C-H a wide range functionalized aryl-, heteroaryl-, alkyl-substituted dioxazolones under conditions. observed regioselectivity towards primary supported by computational studies cyclometalation proposed proceed means an external carboxylate-assisted concerted metalation/deprotonation mechanism. reported rare example use directing group other than commonly used pyridine quinolone classes functionalization first exploit thioamides.

Язык: Английский

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C−H Bond Functionalization by Mechanochemistry

Chemistry - A European Journal, Год журнала: 2017, Номер 23(68), С. 17157 - 17165

Опубликована: Авг. 24, 2017

The advances made in the mechanosynthesis of inorganic and organometallic complexes excellent past developments with metal-catalyzed cross-coupling reactions by high-speed ball milling have sufficienly laid ground work for merging C-H functionalization mechanochemical techniques. In recent years, fast development activation given us examples olefinations, amidations, halogenations, oxidative couplings, among others. This concept article will describe some events that led to activation, current state-of-the-art, present challenges this merge, unique scenarios which mechanochemistry could complement traditional solution-based approaches.

Язык: Английский

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