N-Heterocyclic carbenes as privileged ligands for nickel-catalysed alkene functionalisation

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 52(9), P. 2946 - 2991

Published: Jan. 1, 2023

This review discusses the applications of N-heterocyclic carbene ligands and their influence on reactivity selectivity Ni-catalysed alkene functionalisations.

Language: Английский

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Facile Access to Quaternary Carbon Centers via Ni-Catalyzed Arylation of Alkenes with Organoborons

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

Published: Jan. 16, 2025

Quaternary carbon centers are widespread structural motifs, thus representing extensive interest in organic synthesis. We describe here an efficient nickel-catalyzed intermolecular, Markovnikov-selective arylation of minimally functionalized alkenes with stable organoborons, affording a broad range cyclic or acyclic quaternary under mild conditions. The utilization the diimine ligand is critical for high reactivity and chemoselectivity. Furthermore, using bulky chiral as Ni catalyst, stereocenters can be readily prepared levels enantiocontrol. Mechanism studies suggest that, before protonation, rare nickel shift from alkyl to aryl might occur.

Language: Английский

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Enantio- and Regioselective Ni-Catalyzed para-C–H Alkylation of Pyridines with Styrenes via Intermolecular Hydroarylation

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(30), P. 13643 - 13651

Published: July 20, 2022

Direct asymmetric functionalization of the pyridyl C–H bond represents a longstanding challenge in organic chemistry. We herein describe first enantioselective para-C–H activation pyridines through use Ni–Al bimetallic catalyst system and N-heterocyclic carbene (NHC) ligand for intermolecular hydroarylation styrenes. The reaction procceds high to excellent enantioselectivities (up 98.5:1.5 er) site-selectivities both styrene pyridine components >98:2). Consequently, broad range enantioenriched 1,1-diarylalkanes containing moieties could be prepared single step with 100% atom economy. Computational studies supported mechanism involving ligand-to-ligand H-transfer (LLHT) reductive elimination sequence, LLHT being rate- enantioselectivity-determining step. DFT indicate that π–π stacking interaction between NHC aryl fragment trans-styrenes is critical reactivity enantiocontrol.

Language: Английский

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Catalytic Enantioselective Primary C–H Borylation for Acyclic All-Carbon Quaternary Stereocenters

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(2), P. 1635 - 1643

Published: Jan. 5, 2024

Creating a perfect catalyst to operate enzyme-like chiral recognition has been long-sought aim. A challenging example in this context is constructing acyclic all-carbon quaternary stereogenic centers by transition metal-catalyzed enantioselective C–H activation. We now report highly iridium-catalyzed primary borylation of α-all-carbon substituted 2,2-dimethyl amides enabled tailor-made bidentate boryl ligand (CBL). The success the current transformation attributed CBL/iridium catalyst, which confined pocket. This protocol provides diverse array stereocenters with excellent enantiocontrol and distinct structural features. Computational study reveals that steric hindrance CBL could regulate type dominant orbital interaction between substrate, crucial conferring high induction.

Language: Английский

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Enantioselective Construction of Quaternary Stereocenters via A Chiral Spiro Phosphoric Acid-Assisted Formal Gold Carbene gem-Dialkylation Reaction

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(28), P. 19261 - 19270

Published: July 1, 2024

Enantioselective construction of all-carbon quaternary stereocenters has attracted much attention over the past few decades. A variety catalytic asymmetric methods have been disclosed based on use presynthesized complex reagents that impart congested steric hindrance to reaction center, which generally produce chiral molecules through forming one C-C bond. The readily available could build two bonds same carbonic center with concomitant assembly remains challenging. Herein, we disclose a alkyne multifunctionalization using gold and spiro phosphoric acid (SPA) for synergistic catalysis. In this method, accessible internal alkynes served as key carbene precursors, followed by

Language: Английский

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Enantioselective Ni‐Catalyzed Three‐Component Dicarbofunctionalization of Alkenes

ChemCatChem, Journal Year: 2023, Volume and Issue: 15(18)

Published: Aug. 3, 2023

Abstract Asymmetric multicomponent reactions are considered as efficient protocols for constructing complex chiral molecules because of their step‐ and atom‐economy. Nickel‐catalyzed asymmetric three‐component dicarbofunctionalization alkenes has been well developed in recent years, which is used the area total synthesis natural products late‐stage modification drugs rapid incorporation sp 3 ‐enriched carbon centers. In this concept, significant breakthroughs field summarized, together with related mechanisms. Moreover, remaining challenges potential opportunities also highlighted.

Language: Английский

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Reversible Radical Addition Guides Selective Photocatalytic Intermolecular Thiol‐Yne‐Ene Molecular Assembly

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(13)

Published: Jan. 19, 2024

Abstract In modern organic chemistry, harnessing the power of multicomponent radical reactions presents both significant challenges and extraordinary potential. This article delves into this scientific frontier by addressing critical issue controlling selectivity in such complex processes. We introduce a novel approach that revolves around reversible addition thiyl radicals to multiple bonds, reshaping landscape reactions. The key lies intricate interplay between reversibility energy landscapes governing C−C bond formation thiol‐yne‐ene developed not only allows prioritize cascade, dominating over alternative reactions, but also extends scope coupling products obtained from alkenes alkynes various structures electron density distributions, regardless their relative polarity difference, opening doors more versatile synthetic possibilities. present study, we provide powerful tool for atom‐economical C−S formation, paving way efficient synthesis molecules. Carrying out our experimental computational studies, elucidated fundamental mechanisms underlying cascades, knowledge can be broadly applied field chemistry.

Language: Английский

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Asymmetric Three-Component Reaction to Assemble the Acyclic All-Carbon Quaternary Stereocenter via Visible Light and Phosphoric Acid Catalysis

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(21), P. 13282 - 13291

Published: Oct. 17, 2022

Chiral acyclic all-carbon quaternary stereocenters are widely present in natural products and pharmaceuticals. However, their introduction remains a challenging topic the synthetic research community. Here, we report an efficient metal-free method for construction of chiral centers sited at α-position aldehyde or ketone moiety. This is achieved via well-designed reaction cascade involving arylalkynes, benzoquinones, electron-rich (hetero)arenes use visible light phosphoric acid catalysis. Notably, asymmetric catalytic visible-light-induced Paternò–Büchi cycloaddition/electrocyclic ring-opening/α-selective arylation α,β-unsaturated carbonyl compound cascades achieved. Moreover, works well broad range these three components (>70 examples). Furthermore, rich chemistry embedded provides variety synthetically useful building blocks that otherwise difficult to access. Lastly, origin enantioselectivity was investigated by density functional theory, revealing CH/π interactions play crucial role stereocontrol reaction.

Language: Английский

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Ligand-ligated Ni–Al bimetallic catalysis for C–H and C–C bond activation

Chemical Communications, Journal Year: 2022, Volume and Issue: 58(88), P. 12260 - 12273

Published: Jan. 1, 2022

Compared with non-ligated Ni-Al bimetallic catalysis, bifunctional ligand-ligated catalysis displays stronger synergism, not only affecting the electronic properties and steric hindrance of substrates, but also producing a directing effect for facile control reactivity, site selectivity enantioselectivity in activation C-H C-C bonds. This review will give brief summary research advances this field, highlighting development ligands their applications.

Language: Английский

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Nickel-catalyzed acylzincation of allenes with organozincs and CO

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Oct. 31, 2023

Transition metal-catalyzed carbonylative reaction with CO gas are among the central task in organic synthesis, enabling construction of highly valuable carbonyl compound. Here, we show an earth-abundant nickel-catalyzed three-component tandem acylzincation/cyclization sequence allene and alkylzinc reagent 1 atm under mild conditions. This protocol is featured by broad functional group tolerance high selectivity, providing a rapid convenient synthetic method for diverse fully substituted benzotropone derivatives. Mechanistic studies reveal that installation cyano tethered to moiety enables regio- stereoselectivity this acylzincation allene, allowing selective formation three consecutive C-C bonds efficient manner.

Language: Английский

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