Photocatalytic Late-Stage C–H Functionalization

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(8), P. 4237 - 4352

Published: Jan. 24, 2023

The emergence of modern photocatalysis, characterized by mildness and selectivity, has significantly spurred innovative late-stage C–H functionalization approaches that make use low energy photons as a controllable source. Compared to traditional strategies, photocatalysis paves the way toward complementary and/or previously unattainable regio- chemoselectivities. Merging compelling benefits with workflow offers potentially unmatched arsenal tackle drug development campaigns beyond. This Review highlights photocatalytic strategies small-molecule drugs, agrochemicals, natural products, classified according targeted bond newly formed one. Emphasis is devoted identifying, describing, comparing main mechanistic scenarios. draws critical comparison between established ionic chemistry photocatalyzed radical-based manifolds. aims establish current state-of-the-art illustrate key unsolved challenges be addressed in future. authors aim introduce general readership functionalization, specialist practitioners evaluation methodologies, potential for improvement, future uncharted directions.

Language: Английский

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Enantioselective Radical Reactions Using Chiral Catalysts

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(6), P. 5842 - 5976

Published: Jan. 24, 2022

Benefiting from the impressive increase in fundamental knowledge, last 20 years have shown a continuous burst of new ideas and consequently plethora catalytic methods for enantioselective radical reactions. This review aims to provide complete survey progress achieved over this latter period. The first part focuses on use chiral organocatalysts, these include catalysts covalently linked substrate those that interact with by weaker interactions like hydrogen bonds. second is devoted transition-metal redox catalysis which organized according increasing atomic number first-row transition metals (Ti, Cr, Fe, Mn, Co, Ni, Cu). Bioinspired manganese- iron-mediated hydroxylations oxidations are also discussed. A specific section dedicated reactivity Ru, Rh, Ir complexes as Lewis acids special focus at metal. Absorption photons result different events such energy transfer, single-electron hydrogen-atom transfer facilitating formation radicals. Organocatalysis has been successfully combined photocatalysts, opened pathways enlarging precursors available. merger photocatalysis organo- or metalla-photocatalysis brought novelty allowed discovery large original transformations. enzyme-catalyzed reactions involving intermediates largely benefit visible-light irradiation included review. provides comprehensive inventory goal detailing reaction mechanisms involved transformations any nonspecialist could find their own creativity invent yet unknown applications.

Language: Английский

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Ligand‐to‐Metal Charge Transfer (LMCT) Photochemistry at 3d‐Metal Complexes: An Emerging Tool for Sustainable Organic Synthesis

ChemCatChem, Journal Year: 2022, Volume and Issue: 14(19)

Published: Aug. 11, 2022

Abstract Despite the rich photochemistry of 3d‐metal complexes, utilization excited‐state reactivity these compounds in organic synthesis has been historically overlooked. The advent photoredox catalysis changed perception synthetic chemists towards photochemistry, and nowadays potential photoinduced, outer‐sphere single‐electron transfer events is widely recognized. More recently, an emerging new mode photoactivation taken spotlight, based on inner‐sphere triggered by population ligand‐to‐metal charge‐transfer (LMCT) excited states. Contrarily to photoredox, LMCT‐activation does not rely matching redox potentials, offers unique profiles particularly well suited Earth‐abundant metal complexes. Those appealing features are propelling development methods using this blueprint generate highly reactive open‐shell species under mild conditions. aim contribution provide a didactical tool for comprehension concept facilitate methodologies achieve sustainable chemical transformations.

Language: Английский

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Radical NHC Catalysis

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(19), P. 11984 - 11999

Published: Sept. 19, 2022

Radical/radical cross-coupling reactions represent an efficient and straightforward approach for the construction of chemical bonds accordingly have drawn increasing attention over past decades. In order to achieve synthetically useful transformations, a persistent radical should be coupled with transient in accordance effect (PRE). However, known radicals outnumber by far types free radicals, which limits widespread application PRE, until today. Thus, development between has been focus, meanwhile transition-metal catalysis successfully implemented artificially prolong lifetimes, allowing their utilization formal radical/radical cross-couplings. Complementary research field recently uncovered that organocatalytically generated NHC-derived ketyl are type catalytically radicals. NHC-catalyzed transformations aldehydes carboxylic acid derivatives enabled disclosure ever-increasing number interesting reactions, different from traditional ionic processes, offering otherwise inaccessible activation modes. These discoveries opened door NHC organocatalysis manipulation reactions. Due its obvious potential synthetic organic chemistry, it is timely provide perspective on this emerging field.

Language: Английский

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Photoactive Copper Complexes: Properties and Applications

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(22), P. 16365 - 16609

Published: Nov. 9, 2022

Photocatalyzed and photosensitized chemical processes have seen growing interest recently become among the most active areas of research, notably due to their applications in fields such as medicine, synthesis, material science or environmental chemistry. Among all homogeneous catalytic systems reported date, photoactive copper(I) complexes been shown be especially attractive, not only alternative noble metal complexes, extensively studied utilized recently. They are at core this review article which is divided into two main sections. The first one focuses on an exhaustive comprehensive overview structural, photophysical electrochemical properties mononuclear typical examples highlighting critical structural parameters impact being presented enlighten future design complexes. second section devoted application (photoredox catalysis organic reactions polymerization, hydrogen production, photoreduction carbon dioxide dye-sensitized solar cells), illustrating progression from early current state-of-the-art showcasing how some limitations can overcome with high versatility.

Language: Английский

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Radical C(sp3)–H functionalization and cross-coupling reactions

Nature Reviews Chemistry, Journal Year: 2022, Volume and Issue: 6(6), P. 405 - 427

Published: May 17, 2022

Language: Английский

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Supramolecular Coordination Cages for Artificial Photosynthesis and Synthetic Photocatalysis

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(9), P. 5225 - 5261

Published: Jan. 20, 2023

Because sunlight is the most abundant energy source on earth, it has huge potential for practical applications ranging from sustainable supply to light driven chemistry. From a chemical perspective, excited states generated by make thermodynamically uphill reactions possible, which forms basis storage into fuels. In addition, with light, open-shell species can be open up new reaction pathways in organic synthesis. Crucial are photosensitizers, absorb and transfer substrates various mechanisms, processes that highly depend distance between molecules involved. Supramolecular coordination cages well studied synthetically accessible vessels single cavities guest binding, ensuring close proximity of different components. Due high modularity their size, shape, nature metal centers ligands, ideal platforms exploit preorganization photocatalysis. Herein we focus application supramolecular photocatalysis artificial photosynthesis photo(redox) catalysis. Finally, brief overview immobilization strategies provides tools implementing devices. This review inspiration future design photocatalytic host-guest systems producing solar fuels complex molecules.

Language: Английский

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Nontraditional Fragment Couplings of Alcohols and Carboxylic Acids: C(sp³)–C(sp³) Cross-Coupling via Radical Sorting

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(14), P. 6185 - 6192

Published: March 30, 2022

Alcohols and carboxylic acids are among the most commercially abundant, synthetically versatile, operationally convenient functional groups in organic chemistry. Under visible light photoredox catalysis, these native synthetic handles readily undergo radical activation, resulting open-shell intermediates can subsequently participate transition metal catalysis. In this report, we describe C(sp3)–C(sp3) cross-coupling of alcohols through dual combination N-heterocyclic carbene (NHC)-mediated deoxygenation hypervalent iodine-mediated decarboxylation. This mild practical Ni-catalyzed radical-coupling protocol was employed to prepare a wide array alkyl–alkyl cross-coupled products, including highly congested quaternary carbon centers from corresponding tertiary or acids. We demonstrate applications methodology alcohol C1-alkylation formal homologation, as well late-stage functionalization drugs, natural biomolecules.

Language: Английский

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Carboxylic Acids as Adaptive Functional Groups in Metallaphotoredox Catalysis

Accounts of Chemical Research, Journal Year: 2022, Volume and Issue: 55(23), P. 3481 - 3494

Published: Nov. 22, 2022

The development of palladium-catalyzed cross-coupling methods for the activation C(sp2)-Br bonds facilitated access to arene-rich molecules, enabling a concomitant increase in prevalence this structural motif drug molecules recent decades. Today, there is growing appreciation value incorporating saturated C(sp3)-rich scaffolds into pharmaceutically active as means achieve improved solubility and physiological stability, providing impetus develop new coupling strategies these challenging motifs most straightforward way possible. As an alternative classical two-electron chemistry, redox chemistry can enable elusive transformations, recently, by interfacing abundant first-row transition-metal catalysis with photoredox catalysis. such, functionalization ubiquitous versatile functional handles such (aliphatic) carboxylic acids via metallaphotoredox has emerged valuable field research over past eight years.In Account, we will outline progress methodologies that employ aliphatic (hetero)aromatic adaptive groups. Whereas decarboxylative often necessitate preactivated form redox-active esters or ligands hypervalent iodine reagents, direct use native acid functionality are highly desired have been accomplished through protocols. found bench-stable undergo diverse alkylation, arylation, amination, trifluoromethylation, leveraging prevalent transition metals nickel copper. Likewise, aryl now able halogenation borylation, entry points traditional, primarily palladium- copper-catalyzed strategies. Given breadth group tolerance employed reaction conditions, late-stage toward targets become standard tool design, synthesis various diversified molecules. rapid rise positively inspired pharmaceutical discovery be further accelerated novel development. achievement generality optimization campaigns allows future breakthroughs render protocols more reliable applicable industry. This article intended highlight, particular, (i) employment (hetero)aryl powerful (ii) need still-elusive selective transformations.We strongly believe functionalities inspire researchers across world investigate complex molecular targets.

Language: Английский

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Electrochemical Late-Stage Functionalization

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(19), P. 11269 - 11335

Published: Sept. 26, 2023

Late-stage functionalization (LSF) constitutes a powerful strategy for the assembly or diversification of novel molecular entities with improved physicochemical biological activities. LSF can thus greatly accelerate development medicinally relevant compounds, crop protecting agents, and functional materials. Electrochemical synthesis has emerged as an environmentally friendly platform transformation organic compounds. Over past decade, electrochemical late-stage (eLSF) gained major momentum, which is summarized herein up to February 2023.

Language: Английский

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