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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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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Site‐Selective δ‐C(sp³)−H Alkylation of Amino Acids and Peptides with Maleimides via a Six‐Membered Palladacycle

Angewandte Chemie International Edition, Год журнала: 2018, Номер 57(20), С. 5858 - 5862

Опубликована: Март 26, 2018

The site-selective functionalization of unactivated C(sp3 )-H bonds remains one the greatest challenges in organic synthesis. Herein, we report on δ-C(sp3 alkylation amino acids and peptides with maleimides via a kinetically less favored six-membered palladacycle presence more accessible γ-C(sp3 bonds. Experimental studies revealed that C-H bond cleavage occurs reversibly preferentially at γ-methyl over δ-methyl while subsequent proceeds exclusively is generated by δ-C-H activation. selectivity can be explained Curtin-Hammett principle. exceptional compatibility this various oligopeptides renders procedure valuable for late-stage peptide modifications. Notably, process also first palladium(II)-catalyzed Michael-type reaction through

Язык: Английский

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Transition-metal-catalyzed C–H bond alkylation using olefins: recent advances and mechanistic aspects

Chemical Society Reviews, Год журнала: 2022, Номер 51(17), С. 7358 - 7426

Опубликована: Янв. 1, 2022

Transition metal catalysis has contributed immensely to C-C bond formation reactions over the last few decades, and alkylation is no exception. The superiority of such methodologies traditional evident from minimal reaction steps, shorter times, atom economy while also allowing control regio- stereo-selectivity. In particular, hydrocarbonation alkenes grabbed increased attention due its fundamental ability effectively selectively synthesise a wide range industrially pharmaceutically relevant moieties. This review attempts provide scientific viewpoint systematic analysis recent developments in transition-metal-catalyzed various C-H bonds using simple activated olefins. key features mechanistic studies involved these transformations are described briefly.

Язык: Английский

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Pentamethylcyclopentadienyl rhodium(III)–chiral disulfonate hybrid catalysis for enantioselective C–H bond functionalization

Nature Catalysis, Год журнала: 2018, Номер 1(8), С. 585 - 591

Опубликована: Июль 20, 2018

Язык: Английский

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Beyond Friedel and Crafts: Directed Alkylation of C−H Bonds in Arenes

Angewandte Chemie International Edition, Год журнала: 2018, Номер 58(22), С. 7202 - 7236

Опубликована: Авг. 14, 2018

Abstract Alkylation of arenes is one the most fundamental transformations in chemical synthesis and leads to privileged scaffolds many areas science. Classical methods for introduction alkyl groups are mostly based on Friedel–Crafts reaction, radical additions, metalation, or prefunctionalization arene: these methods, however, suffer from limitations scope, efficiency, selectivity. Moreover, they innate reactivity starting arene, favoring alkylation at a certain position rendering chains other positions much more challenging. This can be addressed by use directing group that facilitates, presence metal catalyst, regioselective C−H bond. These directed alkylations bonds will comprehensively summarized this Review.

Язык: Английский

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Alkylation, Annulation, and Alkenylation of Organic Molecules with Maleimides by Transition‐Metal‐Catalyzed C‐H Bond Activation

Asian Journal of Organic Chemistry, Год журнала: 2019, Номер 8(11), С. 1949 - 1969

Опубликована: Март 13, 2019

Abstract Maleimide and succinimide core moieties are present in various natural products pharmaceuticals. In addition, these derivatives can be readily modified into biologically important organic molecules including pyrrolidines γ‐lactams. A transition‐metal‐catalyzed chelation‐assisted functionalization of inert C−H bond with electrophiles or nucleophiles is one the efficient methods to construct chemical bonds a highly atom‐ step‐economical manner. The review describes recent advances reaction involving maleimides by activation methodology. having directing groups, such as ketone, acyl, pyridyl, pyrimidyl, oxime, amide, imidate, chromone, azo, N ‐sulfonyl ketimine, carboxylic acids, aldimines, were described. scope, limitation mechanistic investigation alkylation, annulation alkenylation reactions discussed elaborately. This article includes entire report on bond‐forming strategy until end 2018.

Язык: Английский

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Cobalt-Catalyzed Enantioselective Hydroarylation of 1,6-Enynes

Journal of the American Chemical Society, Год журнала: 2020, Номер 142(20), С. 9510 - 9517

Опубликована: Апрель 25, 2020

An asymmetric hydroarylative cyclization of enynes involving a C–H bond cleavage is reported. The cobalt-catalyzed cascade generates three new bonds in an atom-economical fashion. products were obtained excellent yields and enantioselectivities as single diastereo- regioisomers. Preliminary mechanistic studies indicate that the reaction shows no intermolecular crossover. This work highlights potential cobalt catalysis functionalization enantioselective domino reactivity.

Язык: Английский

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An Approach to 3-(Indol-2-yl)succinimide Derivatives by Manganese-Catalyzed C–H Activation

Organic Letters, Год журнала: 2017, Номер 19(15), С. 4042 - 4045

Опубликована: Июль 26, 2017

The manganese-catalyzed addition of C-2 position indoles to maleimides has been achieved under additive-free conditions. manganese catalyst exhibits excellent chemo- and regioselectivity, good functional group compatibility, high catalytic efficiency. substrate scope can also be extended maleates, ethyl acrylate, 1,4-dihydro-1,4-epoxynaphthalene, pyrroles, 2-phenylpyridine, which further demonstrates the universality this straightforward approach.

Язык: Английский

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Cobalt-Catalyzed Oxidant-Free Spirocycle Synthesis by Liberation of Hydrogen

Organic Letters, Год журнала: 2017, Номер 19(17), С. 4640 - 4643

Опубликована: Авг. 21, 2017

The first example of oxidant-free cobalt-catalyzed synthesis five-membered spirocycles is reported from benzimidates and maleimides utilizing nitrobenzene as promoter. In contrast to previously known oxidative C–H functionalization reactions, this transformation occurs efficiently in the absence oxidant accompanied by liberation hydrogen. spiro-lactams were readily achieved hydrolysis as-prepared spirocyclic compounds. Cp*Rh(III) catalyst shows poor reactivity.

Язык: Английский

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