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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Metallaphotoredox: The Merger of Photoredox and Transition Metal Catalysis

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(2), P. 1485 - 1542

Published: Nov. 18, 2021

The merger of photoredox catalysis with transition metal catalysis, termed metallaphotoredox has become a mainstay in synthetic methodology over the past decade. Metallaphotoredox combined unparalleled capacity for bond formation broad utility photoinduced electron- and energy-transfer processes. Photocatalytic substrate activation allowed engagement simple starting materials metal-mediated bond-forming Moreover, electron or energy transfer directly key organometallic intermediates provided novel modes entirely complementary to traditional catalytic platforms. This Review details contextualizes advancements molecule construction brought forth by metallaphotocatalysis.

Language: Английский

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Electrochemical strategies for C–H functionalization and C–N bond formation

Chemical Society Reviews, Journal Year: 2018, Volume and Issue: 47(15), P. 5786 - 5865

Published: Jan. 1, 2018

This review provides an overview of the use electrochemistry as appealing platform for expediting carbon–hydrogen functionalization and carbon–nitrogen bond formation.

Language: Английский

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Direct Photocatalyzed Hydrogen Atom Transfer (HAT) for Aliphatic C–H Bonds Elaboration

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(2), P. 1875 - 1924

Published: Aug. 6, 2021

Direct photocatalyzed hydrogen atom transfer (d-HAT) can be considered a method of choice for the elaboration aliphatic C–H bonds. In this manifold, photocatalyst (PCHAT) exploits energy photon to trigger homolytic cleavage such bonds in organic compounds. Selective bond may achieved by judicious abstractor (key parameters are electronic character and molecular structure), as well reaction additives. Different classes PCsHAT available, including aromatic ketones, xanthene dyes (Eosin Y), polyoxometalates, uranyl salts, metal-oxo porphyrin tris(amino)cyclopropenium radical dication. The processes (mainly C–C formation) most cases carried out under mild conditions with help visible light. aim review is offer comprehensive survey synthetic applications d-HAT.

Language: Английский

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Mechanistic Studies in Photocatalysis

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 58(12), P. 3730 - 3747

Published: Oct. 19, 2018

Abstract The fast‐moving fields of photoredox and photocatalysis have recently provided fresh opportunities to expand the potential synthetic organic chemistry. Advances in light‐mediated processes mainly been guided so far by empirical findings quest for reaction invention. general perception, however, is that entering a more mature phase where combination experimental mechanistic studies will play dominant role sustaining further innovation. This Review outlines key consider when developing photochemical process, best techniques available acquiring relevant information. discussion use selected case highlight how investigations can be instrumental guiding invention development synthetically useful photocatalytic transformations.

Language: Английский

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Photocatalytic decarboxylative alkylations mediated by triphenylphosphine and sodium iodide

Science, Journal Year: 2019, Volume and Issue: 363(6434), P. 1429 - 1434

Published: March 28, 2019

Most photoredox catalysts in current use are precious metal complexes or synthetically elaborate organic dyes, the cost of which can impede their application for large-scale industrial processes. We found that a combination triphenylphosphine and sodium iodide under 456-nanometer irradiation by blue light-emitting diodes catalyze alkylation silyl enol ethers decarboxylative coupling with redox-active esters absence transition metals. Deaminative using Katritzky's N-alkylpyridinium salts trifluoromethylation Togni's reagent also demonstrated. Moreover, phosphine/iodide-based system catalyzes Minisci-type N-heterocycles operate tandem chiral phosphoric acids to achieve high enantioselectivity this reaction.

Language: Английский

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Photoredox-Catalyzed C–H Functionalization Reactions

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(2), P. 1925 - 2016

Published: Sept. 29, 2021

The fields of C–H functionalization and photoredox catalysis have garnered enormous interest utility in the past several decades. Many different scientific disciplines relied on strategies including natural product synthesis, drug discovery, radiolabeling, bioconjugation, materials, fine chemical synthesis. In this Review, we highlight use reactions. We separate review into inorganic/organometallic catalysts organic-based catalytic systems. Further subdivision by reaction class─either sp2 or sp3 functionalization─lends perspective tactical for these methods synthetic applications.

Language: Английский

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A Toolbox Approach To Construct Broadly Applicable Metal-Free Catalysts for Photoredox Chemistry: Deliberate Tuning of Redox Potentials and Importance of Halogens in Donor–Acceptor Cyanoarenes

Journal of the American Chemical Society, Journal Year: 2018, Volume and Issue: 140(45), P. 15353 - 15365

Published: Oct. 2, 2018

The targeted choice of specific photocatalysts has been shown to play a critical role for the successful realization challenging photoredox catalytic transformations. Herein, we demonstrate implementation rational design strategy series deliberate structural manipulations cyanoarene-based, purely organic donor-acceptor photocatalysts, using 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) as starting point. Systematic modifications both donor substituents well acceptors' molecular core allowed us identify strongly oxidizing reducing catalysts (e.g., an unprecedented detriflation unactivated naphthol triflate), which additionally offer remarkably balanced redox potentials with predictable trends. Especially halogen arene substitutions are instrumental our alterations catalysts' properties. Based on their preeminent electrochemical and photophysical characteristics, all novel, were evaluated in three challenging, mechanistically distinct classes benchmark reactions (either requiring balanced, highly or properties) enormous potential customizable that outperform complement prevailing typical best photocatalysts.

Language: Английский

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Late-stage C–H functionalization offers new opportunities in drug discovery

Nature Reviews Chemistry, Journal Year: 2021, Volume and Issue: 5(8), P. 522 - 545

Published: July 13, 2021

Language: Английский

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Copper’s rapid ascent in visible-light photoredox catalysis

Science, Journal Year: 2019, Volume and Issue: 364(6439)

Published: May 2, 2019

Visible-light photoredox catalysis offers a distinct activation mode complementary to thermal transition metal catalyzed reactions. The vast majority of processes capitalizes on precious ruthenium(II) or iridium(III) complexes that serve as single-electron reductants oxidants in their photoexcited states. As low-cost alternative, organic dyes are also frequently used but general suffer from lower photostability. Copper-based photocatalysts rapidly emerging, offering not only economic and ecological advantages otherwise inaccessible inner-sphere mechanisms, which have been successfully applied challenging transformations. Moreover, the combination conventional with copper(I) copper(II) salts has emerged an efficient dual catalytic system for cross-coupling

Language: Английский

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