Transition Metal Catalysis Controlled by Hydrogen Bonding in the Second Coordination Sphere

Chemical Reviews, Год журнала: 2022, Номер 122(14), С. 12308 - 12369

Опубликована: Май 20, 2022

Transition metal catalysis is of utmost importance for the development sustainable processes in academia and industry. The activity selectivity complexes are typically result interplay between ligand properties. As can be chemically altered, a large research focus has been on development. More recently, it recognized that further control over achieved by using “second coordination sphere”, which seen as region beyond direct sphere center. Hydrogen bonds appear to very useful interactions this context they have sufficient strength directionality exert second sphere, yet hydrogen dynamic, allowing fast turnover. In review we highlighted several key features bonding summarized use program sphere. Such bridging two ligands coordinated center effectively lead supramolecular bidentate ligands. addition, used preorganize substrate Both strategies catalysts with superior properties variety catalyzed transformations, including (asymmetric) hydrogenation, hydroformylation, C–H activation, oxidation, radical-type photochemical reactions.

Язык: Английский

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Asymmetric intermolecular allylic C–H amination of alkenes with aliphatic amines

Science, Год журнала: 2022, Номер 378(6625), С. 1207 - 1213

Опубликована: Дек. 15, 2022

Aliphatic allylic amines are found in a great variety of complex and biorelevant molecules. The direct C-H amination alkenes serves as the most straightforward method toward these motifs. However, use widely available internal with aliphatic this transformation remains synthetic challenge. In particular, palladium catalysis faces twin challenges inefficient coordination Pd(II) to but excessively tight therefore inhibitory by basic amines. We report general solution problems. developed protocol, contrast classical Pd(II/0) scenario, operates through blue light-induced Pd(0/I/II) manifold mild aryl bromide oxidant. This open-shell approach also enables enantio- diastereoselective amination.

Язык: Английский

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Recent advances in the electrochemical generation of 1,3-dicarbonyl radicals from C–H bonds

Organic Chemistry Frontiers, Год журнала: 2023, Номер 10(11), С. 2830 - 2848

Опубликована: Янв. 1, 2023

Recent advances in the electrochemical generation of 1,3-dicarbonyl radicals from C–H bonds and their mechanistic insights synthetic applications have been summarized.

Язык: Английский

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Recent Advances in Visible Light Induced Palladium Catalysis

Angewandte Chemie International Edition, Год журнала: 2023, Номер 63(9)

Опубликована: Ноя. 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.

Язык: Английский

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Strategies for chiral separation: from racemate to enantiomer

Chemical Science, Год журнала: 2023, Номер 14(43), С. 11955 - 12003

Опубликована: Янв. 1, 2023

Research progress and potential trends about six critical chiral resolution methods are summarized. Notable performance improvements based on the state-of-the-art “coupling” strategies highlighted.

Язык: Английский

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Alcohols as Substrates in Transition-Metal-Catalyzed Arylation, Alkylation, and Related Reactions

Chemical Reviews, Год журнала: 2024, Номер 124(9), С. 6078 - 6144

Опубликована: Апрель 17, 2024

Alcohols are abundant and attractive feedstock molecules for organic synthesis. Many methods their functionalization require them to first be converted into a more activated derivative, while recent years have seen vast increase in the number of complexity-building transformations that directly harness unprotected alcohols. This Review discusses how transition metal catalysis can used toward this goal. These broadly classified three categories. Deoxygenative functionalizations, representing derivatization C–O bond, enable alcohol act as leaving group formation new C–C bonds. Etherifications, characterized by O–H represent classical reactivity has been modernized include mild reaction conditions, diverse partners, high selectivities. Lastly, chain reactions described, wherein acts mediator formal C–H alkyl backbone. Each these classes transformation will discussed context intermolecular arylation, alkylation, related reactions, illustrating alcohols harnessed

Язык: Английский

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

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(17), С. 12053 - 12062

Опубликована: Апрель 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.

Язык: Английский

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Interrupting Associative π–σ–π Isomerization Enables Z-Retentive Asymmetric Tsuji–Trost Reaction

Journal of the American Chemical Society, Год журнала: 2025, Номер 147(3), С. 2776 - 2785

Опубликована: Янв. 8, 2025

The asymmetric Tsuji-Trost reaction has been extensively studied due to its importance in establishing stereogenic centers, often adjacent an E-olefin moiety organic molecules. generally preferential formation of chiral products is believed result from the thermodynamically more stable syn-π-allylpalladium intermediate. rapid associative π-σ-π isomerization makes it challenging synthesize Z-olefin via transient anti-π-allylpalladium Herein, we report a strategy for regulating by tuning steric bulkiness ligands, allylic leaving groups, and counteranions. utilization Pd catalyst derived phosphoramidite ligands interrupts isomerization, enabling highly efficient Z-retentive toward array α-amino acid derivatives bearing motif high yields (up 95%) excellent stereoselectivity 99% ee >19:1 Z/E) with low loading (0.1 mol %). mechanistic insights design reported this work pave way rational developments Tsuji-Trost-type reactions.

Язык: 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, Год журнала: 2025, Номер unknown

Опубликована: Янв. 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.

Язык: Английский

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Ternary Catalysis Enabled Three-Component Asymmetric Allylic Alkylation as a Concise Track to Chiral α,α-Disubstituted Ketones

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(49), С. 20818 - 20827

Опубликована: Дек. 6, 2021

Multicomponent reactions that involve interception of onium ylides through Aldol, Mannich, and Michael addition with corresponding bench-stable acceptors have demonstrated broad applications in synthetic chemistry. However, because the high reactivity transient survival these situ generated intermediates, substitution-type process, especially asymmetric catalytic version, remains hitherto unknown. Herein, a three-component allylation α-diazo carbonyl compounds alcohols allyl carbonates is disclosed by employing ternary cooperative catalysis achiral Pd-complex, Rh2(OAc)4, chiral phosphoric acid CPA. This method represents first example allylic alkylation an SN1-type trapping which involves convergent assembly two active Pd-allyl species, enol derived from ylides, providing expeditious access to α,α-disubstituted ketones good yields excellent enantioselectivity. Combined experimental computational studies shed light on mechanism this novel reaction, including critical role Xantphos ligand origin

Язык: Английский

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