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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Electrocatalysis as an enabling technology for organic synthesis

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(14), P. 7941 - 8002

Published: Jan. 1, 2021

Electrochemistry has recently gained increased attention as a versatile strategy for achieving challenging transformations at the forefront of synthetic organic chemistry. Electrochemistry's unique ability to generate highly reactive radical and ion intermediates in controlled fashion under mild conditions inspired development number new electrochemical methodologies preparation valuable chemical motifs. Particularly, recent developments electrosynthesis have featured an use redox-active electrocatalysts further enhance control over selective formation downstream reactivity these intermediates. Furthermore, electrocatalytic mediators enable proceed manner that is mechanistically distinct from purely methods, allowing subversion kinetic thermodynamic obstacles encountered conventional synthesis. This review highlights key innovations within past decade area electrocatalysis, with emphasis on mechanisms catalyst design principles underpinning advancements. A host oxidative reductive are discussed grouped according classification transformation nature electrocatalyst.

Language: Английский

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Electrocatalytic C–H Activation

ACS Catalysis, Journal Year: 2018, Volume and Issue: 8(8), P. 7086 - 7103

Published: June 18, 2018

C–H activation has emerged as a transformative tool in molecular synthesis, but until recently oxidative activations have largely involved the use of stoichiometric amounts expensive and toxic metal oxidants, compromising overall sustainable nature chemistry. In sharp contrast, electrochemical been identified more efficient strategy that exploits storable electricity place byproduct-generating chemical reagents. Thus, transition-metal catalysts were shown to enable versatile reactions manner. While palladium catalysis set stage for C(sp2)–H C(sp3)–H functionalizations by N-containing directing groups, rhodium ruthenium allowed weakly coordinating amides acids. contrast these precious 4d transition metals, recent year witnessed emergence cobalt oxygenations, nitrogenations, C–C-forming [4+2] alkyne annulations. Thereby, silver(I) oxidants was prevented, improving environmentally benign catalysis. Herein, we summarize major advances organometallic otherwise inert bonds electrocatalysis through May 2018.

Language: Английский

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Metalla-electrocatalyzed C–H Activation by Earth-Abundant 3d Metals and Beyond

Accounts of Chemical Research, Journal Year: 2019, Volume and Issue: 53(1), P. 84 - 104

Published: Dec. 19, 2019

To improve the efficacy of molecular syntheses, researchers wish to capitalize upon selective modification otherwise inert C-H bonds. The past two decades have witnessed considerable advances in coordination chemistry that set stage for transformative tools functionalizations. Particularly, oxidative C-H/C-H and C-H/Het-H transformations gained major attention because they avoid all elements substrate prefunctionalization. Despite advances, activations been dominated by precious transition metal catalysts based on palladium, ruthenium, iridium, rhodium, thus compromising sustainable nature overall activation approach. same holds true predominant use stoichiometric chemical oxidants regeneration active catalyst, prominently featuring hypervalent iodine(III), copper(II), silver(I) oxidants. Thereby, quantities undesired byproducts are generated, which preventive applications scale. In contrast, elegant merger homogeneous metal-catalyzed with electrosynthesis bears unique power achieve outstanding levels oxidant resource economy. Thus, contrast classical electrosyntheses control, metalla-electrocatalysis huge largely untapped potential unmet site selectivities means catalyst control. While indirect electrolysis using palladium complexes has realized, less toxic expensive base feature distinct beneficial assets toward this Account, I summarize emergence electrocatalyzed earth-abundant 3d metals beyond, a topical focus contributions from our laboratories through November 2019. cobalt electrocatalysis was identified as particularly powerful platform wealth transformations, including oxygenations nitrogenations well alkynes, alkenes, allenes, isocyanides, carbon monoxide, among others. As complementary tools, nickel, copper, very recently iron devised metalla-electrocatalyzed activations. Key success were detailed mechanistic insights, oxidation-induced reductive elimination scenarios. Likewise, development methods make weak O-coordination benefited crucial insights into catalyst's modes action experiment, operando spectroscopy, computation. Overall, thereby syntheses These electrooxidative frequently characterized improved chemoselectivities. Hence, ability dial redox at minimum level required desired transformation renders an ideal functionalization structurally complex molecules sensitive functional groups. This strategy was, inter alia, successfully applied scale-up continuous flow step-economical assembly polycyclic aromatic hydrocarbons.

Language: Английский

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C−H Functionalisation for Hydrogen Isotope Exchange

Angewandte Chemie International Edition, Journal Year: 2017, Volume and Issue: 57(12), P. 3022 - 3047

Published: Oct. 12, 2017

The various applications of hydrogen isotopes (deuterium, D, and tritium, T) in the physical life sciences demand a range methods for their installation an array molecular architectures. In this Review, we describe recent advances synthetic C-H functionalisation isotope exchange.

Language: Английский

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Recent Advances in Hydrometallation of Alkenes and Alkynes via the First Row Transition Metal Catalysis

Chinese Journal of Chemistry, Journal Year: 2018, Volume and Issue: 36(11), P. 1075 - 1109

Published: Aug. 20, 2018

Abstract Hydrometallation of alkenes and alkynes provides a straightforward route to access alkyl‐ or alkenyl‐metal reagents, which have wide range applications in organic transformations. In recent years, the first row transition metals (such as copper, nickel, cobalt, iron, etc .) emerged high activity selectivity this area with aid variety ligands. This review covers advances hydrometallation minimally functionalized unsaturated C—C bonds (including alkenes, alkynes, dienes, allenes, enynes, .), well transformations involving catalytic process via metal catalysis.

Language: Английский

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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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Electrochemical Cobalt-Catalyzed C–H Oxygenation at Room Temperature

Journal of the American Chemical Society, Journal Year: 2017, Volume and Issue: 139(51), P. 18452 - 18455

Published: Nov. 18, 2017

Electrochemical cobalt-catalyzed C–H functionalizations were achieved in terms of oxygenation under mild conditions at 23 °C. The robust electrochemical functionalization was characterized by ample substrate scope, whereas mechanistic studies provided support for a facile cleavage. proved viable on arenes and alkenes with excellent levels positional diastereo-selectivity, avoiding the use stoichiometric silver(I) oxidants ambient conditions.

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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