Recent Advances in Visible Light Induced Palladium Catalysis

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 63(9)

Published: Nov. 14, 2023

Visible light-induced Pd catalysis has emerged as a promising subfield of photocatalysis. The hybrid nature radical species enabled wide array radical-based transformations otherwise challenging or unknown via conventional chemistry. In parallel to the ongoing pursuit alternative, readily available precursors, notable discoveries have demonstrated that photoexcitation can alter not only oxidative addition but also other elementary steps. This Minireview highlights recent progress in this area.

Language: Английский

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Photocatalyzed Enantioselective Functionalization of C(sp³)–H Bonds

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(2), P. 1209 - 1223

Published: Jan. 3, 2024

Owing to its diverse activation processes including single-electron transfer (SET) and hydrogen-atom (HAT), visible-light photocatalysis has emerged as a sustainable efficient platform for organic synthesis. These provide powerful avenue the direct functionalization of C(sp3)–H bonds under mild conditions. Over past decade, there have been remarkable advances in enantioselective bond via combined with conventional asymmetric catalysis. Herein, we summarize involving discuss two main pathways this emerging field: (a) SET-driven carbocation intermediates are followed by stereospecific nucleophile attacks; (b) photodriven alkyl radical further enantioselectively captured (i) chiral π-SOMOphile reagents, (ii) stereoselective transition-metal complexes, (iii) another distinct stereoscopic species. We aim key reaction design, catalyst development, mechanistic understanding, new insights into rapidly evolving area research.

Language: Английский

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Photoinduced Pd-Catalyzed Enantioselective Carboamination of Dienes via Aliphatic C–H Bond Elaboration

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(17), P. 12053 - 12062

Published: April 16, 2024

Three-component diene carboaminations offer a potent means to access synthetically valuable allylic amines with rapid molecular complexity escalation. The existing literature primarily discloses racemic examples, necessitating the use of halides/pseudohalides as substrates. This paper introduces photoinduced Pd-catalyzed enantioselective three-component carboamination aryl-substituted 1,3-dienes, leveraging aliphatic C–H bonds for synthesis. reaction employs 10 mol % chiral palladium catalyst and an excess aryl bromide HAT reagent. approach yields diverse allylamines moderate excellent enantioselectivities. Notably, it stands first instance asymmetric reaction, directly utilizing abundant C(sp3)–H bearing partners, such toluene-type substrates, ethers, amines, esters, ketones. protocol exhibits versatility across encompassing aliphatic, aromatic, primary, secondary derivatives. method could serve versatile platform stereoselective incorporation various nucleophiles, dienes, partners.

Language: Английский

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1,4‐Aminoarylation of Butadienes via Photoinduced Palladium Catalysis

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(14)

Published: Feb. 9, 2024

Abstract A visible‐light‐induced, three‐component palladium‐catalyzed 1,4‐aminoarylation of butadienes with readily available aryl halides and aliphatic amines has been developed, affording allylamines excellent E ‐selectivity. The reaction exhibits exceptional control over chemo‐, regio‐, stereoselectivity, a broad substrate scope, high functional group compatibility, as demonstrated by the late‐stage functionalization bioactive molecules. Mechanistic investigations are consistent photoinduced radical Pd(0)‐Pd(I)‐Pd(II)‐Pd(0) Heck‐Tsuji–Trost allylation cascade.

Language: Английский

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Photoinduced Regiodivergent and Enantioselective Cross-Coupling of Glycine Derivatives with Hydrocarbon Feedstocks

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 2, 2025

Regiodivergent asymmetric synthesis represents a transformative strategy for the efficient generation of structurally diverse chiral products from single set starting materials, significantly enriching their enantiomeric composition. However, design radical-mediated regiodivergent and enantioselective reactions that can accommodate wide range functional groups substrates has posed significant challenges. The obstacles primarily lie in switching regioselectivity achieving high enantiodiscrimination, especially when dealing with high-energy intermediates. To address these issues, we have developed new catalytic system integrates photoinduced hydrogen atom transfer (HAT) copper catalysis, involving fine-tuning ligands, additives, other reaction parameters. facilitates cross-couplings between N-aryl glycine ester/amide derivatives abundant hydrocarbon feedstocks through strong C(sp3)–H bond activation. This approach allows controlled stereoselective formation C(sp3)–C(sp3) C(sp3)–N bonds, yielding rich variety C- or N-alkylated esters amides commendable yields (up to 92% yield), exclusive regioselectivities (typically >20:1 rr), enantioselectivities 96% ee). Our methodology not only provides promising avenue incorporation alkyl functionalities onto specific sites biologically molecules but also offers practical while simultaneously induction within photochemical reactions.

Language: Английский

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General (hetero)polyaryl amine synthesis via multicomponent cycloaromatization of amines

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 2, 2025

Language: Английский

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Catalysis in the Excited State: Bringing Innate Transition Metal Photochemistry into Play

ACS Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 4665 - 4680

Published: March 5, 2025

Transition metal catalysis is an indispensable tool for organic synthesis that has been harnessed, modulated, and perfected many decades by careful selection of centers ligands, giving rise to synthetic methods with unparalleled efficiency chemoselectivity. Recent developments have demonstrated how light irradiation can also be recruited as a powerful dramatically alter the outcome catalytic reactions, providing access innovative pathways remarkable potential. In this context, adoption photochemical conditions mainstream strategy drive reactions unveiled exciting opportunities exploit rich excited-state framework transition metals applications. This Perspective examines advances in application complexes standalone photocatalysts, exploiting innate reactivity their excited states beyond common use photoredox catalysts. An account relevant examples dissected provide discussion on electronic reorganization, orbitals involved, associated different types states. analysis aims practitioners fundamental principles guiding strategies understand, design, apply light-activation homogeneous synthesis.

Language: Английский

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Merging of Light/Dark Palladium Catalytic Cycles Enables Multicomponent Tandem Alkyl Heck/Tsuji–Trost Homologative Amination Reaction toward Allylic Amines

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(33), P. 18497 - 18505

Published: Aug. 9, 2023

A visible light-induced palladium-catalyzed homologative three-component synthesis of allylic amines has been developed. This protocol proceeds

Language: Английский

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Enhanced Excited-State Hydricity of Pd–H Allows for Unusual Head-to-Tail Hydroalkenylation of Alkenes

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(22), P. 12224 - 12232

Published: May 24, 2023

Photoinduced enhancement of hydricity palladium hydride species enables unprecedented addition-like (“hydridic”) hydropalladation electron-deficient alkenes, which allows for chemoselective head-to-tail cross-hydroalkenylation and electron-rich alkenes. This mild general protocol works with a wide range densely functionalized complex Notably, this approach also highly challenging cross-dimerization electronically diverse vinyl arenes heteroarenes.

Language: Английский

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Recent Advances in C–H Functionalisation through Indirect Hydrogen Atom Transfer

Molecules, Journal Year: 2023, Volume and Issue: 28(16), P. 6127 - 6127

Published: Aug. 18, 2023

The functionalisation of C–H bonds has been an enormous achievement in synthetic methodology, enabling new retrosynthetic disconnections and affording simple equivalents for synthons. Hydrogen atom transfer (HAT) is a key method forming alkyl radicals from substrates. Classic reactions, including the Barton nitrite ester reaction Hofmann–Löffler–Freytag reaction, among others, provided early examples HAT. However, recent developments photoredox catalysis electrochemistry have made HAT powerful tool capable introducing wide range functional groups into bonds. Moreover, greater mechanistic insights stimulated development increasingly site-selective protocols. Site-selectivity can be achieved through tuning electron density at certain using additives, judicious choice reagent, solvent system. Herein, we describe latest methods functionalizing C–H/Si–H/Ge–H indirect between 2018–2023, as well critical discussion reagents, aspects, substrate scopes, background contexts

Language: Английский

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