3d Transition Metals for C–H Activation

Chemical Reviews, Journal Year: 2018, Volume and Issue: 119(4), P. 2192 - 2452

Published: Nov. 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.

Language: Английский

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A comprehensive overview of directing groups applied in metal-catalysed C–H functionalisation chemistry

Chemical Society Reviews, Journal Year: 2018, Volume and Issue: 47(17), P. 6603 - 6743

Published: Jan. 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.

Language: Английский

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Catalytic Transformations of Functionalized Cyclic Organic Carbonates

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(42), P. 13735 - 13747

Published: June 6, 2018

Functionalized cyclic organic carbonates and related heterocycles have emerged as highly versatile heterocyclic substrates for ring-opening decarboxylative catalytic transformations allowing the development of new stereo- enantioselective C-N, C-O, C-C, C-S C-B bond formation reactions. Transition-metal-mediated conversions only recently been rejuvenated powerful approaches towards preparation more complex molecules. This minireview will highlight potential structurally with a focus on their synthetic value mechanistic manifolds that are involved upon conversion.

Language: Английский

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Inert C–H Bond Transformations Enabled by Organometallic Manganese Catalysis

Accounts of Chemical Research, Journal Year: 2018, Volume and Issue: 51(3), P. 816 - 827

Published: Feb. 14, 2018

ConspectusTraditional organic synthesis relies heavily on the transformations of various preinstalled functional groups, such as cross-coupling reactions using organohalides and organometallic reagents. The strategy C–H activation enables direct formation C–C/C–X (X = heteroatom) bonds from inert bonds, which can enhance atom- step-economy synthesis. To date, precious metals have overwhelmingly dominated field; however, rarity high cost these necessitate development more sustainable catalysts. In this regard, catalysts based manganese are highly desirable owing to abundant reserve in earth's crust its economic benefits, low toxicity, potentially unique reactivity. Although first stoichiometric manganese-mediated reaction was reported early 1970, manganese-catalyzed largely underdeveloped. How construct an efficient catalytic cycle for remains a key issue be addressed.In Account, we summarize our recent advances bonds. overcome challenges associated with building manganese-based cycles, developed two novel strategies, namely, synergy between bases (with or w/o bases) acids. By implementing former strategy, cooperative manganese/base systems that facilitate new mode bond by via redox-neutral base-assisted deprotonation mechanism. As such, requirement tedious preparation MnR(CO)5 complexes (R Me, Bn, Ph) eliminated, series arenes partners having C≡C C═C were achieved. Through latter acids, disclosed "dual activation" performing transformations, is, merging C–X multiple Lewis Consequently, scope substrates could expanded include challenging ketones olefinic compounds. Additionally, range significantly broadened those bearing polarized C═O, C═N, C≡N aldehydes, imines, nitriles. Remarkably, innate reactivity different reversed catalysis, even carried out at room temperature. Our findings provide guiding information future beyond. Related important contributions other groups mentioned, remaining perspective emerging area also presented.

Language: Английский

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Flow Rhodaelectro-Catalyzed Alkyne Annulations by Versatile C–H Activation: Mechanistic Support for Rhodium(III/IV)

Journal of the American Chemical Society, Journal Year: 2019, Volume and Issue: 141(43), P. 17198 - 17206

Published: Sept. 24, 2019

A flow-metallaelectro-catalyzed C–H activation was realized in terms of robust rhodaelectro-catalyzed alkyne annulations. To this end, a modular electro-flow cell with porous graphite felt anode designed to ensure efficient turnover. Thereby, variety C–H/N–H functionalizations proved amenable for annulations high levels regioselectivity and functional group tolerance, viable both an inter- or intramolecular manner. The allowed easy scale up, while in-operando kinetic analysis accomplished by online flow-NMR spectroscopy. Mechanistic studies suggest oxidatively induced reductive elimination pathway on rhodium(III) electrocatalytic regime.

Language: Английский

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C–H functionalization reactions under flow conditions

Chemical Society Reviews, Journal Year: 2019, Volume and Issue: 48(10), P. 2767 - 2782

Published: Jan. 1, 2019

This review summarizes the application of flow technologies for realization C–H functionalization reactions, focusing on main features and benefits use compared to batch conditions.

Language: Английский

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Late‐Stage Diversification through Manganese‐Catalyzed C−H Activation: Access to Acyclic, Hybrid, and Stapled Peptides

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 58(11), P. 3476 - 3480

Published: Dec. 19, 2018

Abstract Bioorthogonal C−H allylation with ample scope was accomplished through a versatile manganese(I)‐catalyzed activation for the late‐stage diversification of structurally complex peptides. The unique robustness manganese(I) catalysis manifold reflected by full tolerance sensitive functional groups, such as iodides, esters, amides, and OH‐free hydroxy thereby setting stage racemization‐free synthesis fused peptide hybrids featuring steroids, drug molecules, natural products, nucleobases, saccharides.

Language: Английский

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Biomass-Derived Solvents for Sustainable Transition Metal-Catalyzed C–H Activation

ACS Sustainable Chemistry & Engineering, Journal Year: 2019, Volume and Issue: 7(9), P. 8023 - 8040

Published: March 29, 2019

Transition metal-catalyzed C–H activation has emerged as an increasingly powerful strategy in molecular syntheses and a particularly attractive alternative to classical methods of cross-couplings. During the recent years, significant focus been dedicated further improve sustainable nature approach. As solvents represent major portion organic pollution caused by chemical syntheses, range nontoxic, biobased, have developed substitute for common reaction media. In this review, we present general perspective biomass-derived transition reactions their unique potential up January 2019.

Language: Английский

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Manganese(I)‐Catalyzed C−H (2‐Indolyl)methylation: Expedient Access to Diheteroarylmethanes

Angewandte Chemie International Edition, Journal Year: 2017, Volume and Issue: 57(5), P. 1399 - 1403

Published: Dec. 5, 2017

An unprecedented MnI -catalyzed (2-indolyl)methylation of heteroarenes is reported. This method makes use an aromatizing cascade strategy to install a (2-indolyl)methyl group into target molecules, thereby leading the expedient synthesis previously challenging and important unsymmetrical diheteroarylmethanes, in particular bis(2-indolyl)methanes. The proposed process comprises reorganization multiple bonds with controlled regioselectivity high atom economy can be performed on gram-scale. Furthermore, metal-free C-H propargylation observed. diverse application this also demonstrated.

Language: Английский

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Continuous Visible‐Light Photoflow Approach for a Manganese‐Catalyzed (Het)Arene C−H Arylation

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(33), P. 10625 - 10629

Published: June 8, 2018

Abstract Manganese photocatalysts enabled versatile room‐temperature C−H arylation reactions by means of continuous visible‐light photoflow, thus allowing for efficient arylations in 30 minutes with ample scope. The robustness the manganese‐catalyzed photoflow strategy was shown visible light‐induced gram‐scale synthesis, clearly outperforming batch performance.

Language: Английский

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