Mechanistic snapshots of rhodium-catalyzed acylnitrene transfer reactions

Science, Journal Year: 2023, Volume and Issue: 381(6657), P. 525 - 532

Published: July 20, 2023

Rhodium (Rh) acylnitrene complexes are widely implicated in catalytic C-H amidation reactions but have eluded isolation and structural characterization. To overcome this challenge, we designed a chromophoric octahedral Rh complex with bidentate dioxazolone ligand, which photoinduced metal-to-ligand charge transfer initiates amidation. X-ray photocrystallographic analysis of the Rh-dioxazolone allowed elucidation targeted Rh-acylnitrenoid provided firm evidence that singlet nitrenoid species is primarily responsible for acylamino reactions. We also monitored crystallo reaction nucleophile situ-generated Rh-acylnitrenoid, crystallographically traceable system to capture mechanistic snapshots transfer.

Language: Английский

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A New Age of Biocatalysis Enabled by Generic Activation Modes

JACS Au, Journal Year: 2024, Volume and Issue: 4(6), P. 2068 - 2080

Published: May 31, 2024

Biocatalysis is currently undergoing a profound transformation. The field moves from relying on nature's chemical logic to discipline that exploits generic activation modes, allowing for novel biocatalytic reactions and, in many instances, entirely new chemistry. Generic modes enable wide range of reaction types and played pivotal role advancing the fields organo- photocatalysis. This perspective aims summarize principal harnessed enzymes develop biocatalysts. Although extensively researched past, highlighted when applied within enzyme active sites, facilitate transformations have largely eluded efficient selective catalysis. advance attributed multiple tunable interactions substrate binding pocket precisely control competing pathways transition states. We will highlight cases synthetic methodologies achieved by engineered provide insights into potential future developments this rapidly evolving field.

Language: Английский

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Catalytic, asymmetric carbon–nitrogen bond formation using metal nitrenoids: from metal–ligand complexes via metalloporphyrins to enzymes

Chemical Science, Journal Year: 2023, Volume and Issue: 14(44), P. 12447 - 12476

Published: Jan. 1, 2023

The introduction of nitrogen atoms into small molecules is fundamental importance and it vital that ever more efficient selective methods for achieving this are developed. With aim, the potential nitrene chemistry has long been appreciated but its application constrained by extreme reactivity these labile species. This liability however can be attenuated complexation with a transition metal resulting nitrenoids have unique highly versatile which includes amination certain types aliphatic C-H bonds as well reactions alkenes to afford aziridines. At least one new chiral centre typically formed in processes development catalysts exert control over enantioselectivity nitrenoid-mediated become growing area research, particularly past two decades. Compared some synthetic methods, nitrenoid notable chemists draw from diverse array metals , ranging metal-ligand complexes, bearing variety ligand types, via bio-inspired metalloporphyrins, all way through to, very recently, engineered enzymes themselves. In latter category particular, rapid progress being made, rate suggests approach may instrumental addressing outstanding challenges field. review covers key developments strategies shaped field, addition latest advances, up until September 2023.

Language: Английский

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Artificial Metalloenzyme-Catalyzed Enantioselective Amidation via Nitrene Insertion in Unactivated C(sp³)–H Bonds

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(30), P. 16621 - 16629

Published: July 20, 2023

Enantioselective C–H amidation offers attractive means to assemble C–N bonds synthesize high-added value, nitrogen-containing molecules. In recent decades, complementary enzymatic and homogeneous-catalytic strategies for have been reported. Herein, we report on an artificial metalloenzyme (ArM) resulting from anchoring a biotinylated Ir-complex within streptavidin (Sav). The ArM catalyzes the enantioselective of unactivated C(sp3)–H bonds. Chemogenetic optimization Ir cofactor Sav led significant improvement in both activity enantioselectivity. Up >700 TON 92% ee was achieved. single crystal X-ray analysis nitrene insertase (ANIase) combined with quantum mechanics-molecular mechanics (QM-MM) calculations sheds light critical second coordination sphere contacts leading improved catalytic performance.

Language: Английский

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Ligand‐Promoted Iron‐Catalyzed Nitrene Transfer for the Synthesis of Hydrazines and Triazanes through N‐Amidation of Arylamines

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 63(2)

Published: Nov. 24, 2023

Abstract Herein, we report that bulky alkylphosphines such as P t Bu 3 can switch the roles from actor to spectator ligands promote FeCl 2 ‐catalyzed N ‐amidation reaction of arylamines with dioxazolones, giving hydrazides in high efficiency and chemoselectivity. Mechanistic studies indicated phosphine could facilitate decarboxylation dioxazolones on Fe center, hydrogen bonding interactions between nitrenoid intermediates might play a role modulating delicate interplay ligand, arylamine, acyl nitrene N, favoring N−N coupling over N−P coupling. The new ligand‐promoted protocols offer convenient way access various challenging triazane compounds via double or sequential primary arylamines.

Language: Английский

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The Indenyl Effect: Accelerated C−H Amidation of Arenes via Ind*Rh^III Nitrene Transfer Catalysis**

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(23)

Published: April 6, 2023

Investigations into C-H amidation reactions catalysed by cationic half-sandwich d6 metal complexes revealed that the indenyl-derived catalyst [Ind*RhCl2 ]2 significantly accelerated directed ortho of benzoyl silanes using 1,4,2-dioxazol-5-ones. Ring slippage involving a haptotropic η5 to η3 rearrangement indenyl complex proposedly enables ligand substitution at centre proceed via associative, rather than dissociative pathways, leading significant rate and yield enhancements. Intriguingly, this phenomenon appears specific for weakly coordinating carbonyl-based directing groups with no acceleration observed corresponding strongly nitrogen-based groups.

Language: Английский

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Ruthenium-Catalyzed γ-Selective Intermolecular Amidation of Nonactivated Distal Methylene C–H Bonds of Terminal Alkenes via Olefin Chain-Walking Isomerization

ACS Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 3980 - 3991

Published: Feb. 20, 2025

Language: Английский

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Synergistic Photoredox and Electrochemical Catalysis in Organic Synthesis and Late‐Stage Functionalizations

ChemCatChem, Journal Year: 2024, Volume and Issue: 16(14)

Published: Feb. 7, 2024

Abstract This review delves into the innovative field of interfacial photoelectrochemical (iPEC) and (PEC) catalysis, dynamic synthesis methodologies that seamlessly integrates electrochemical photoredox catalysis for efficient environmentally friendly reactions. Utilizing minute quantities photocatalysts, visible light becomes a powerful tool, generating transient excited states to catalyze spectrum reactions through single‐electron oxidation or reduction events. The categorizes recent advancements, highlighting applications in organic synthesis, late‐stage modifications, distinctive features methodology. Despite being its early stages, this synergistic approach holds great promise propelling forward, with potential large‐scale diverse functionalizations, including asymmetric bioconjugation strategies biomolecule modifications.

Language: Английский

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Iron-Catalyzed Primary Amination of C(sp³)–H Bonds

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(36), P. 24863 - 24870

Published: Aug. 28, 2024

Primary amines are privileged molecules in drug development. Yet, there is a noticeable scarcity of methods for directly introducing primary amine group into the ubiquitous C(sp

Language: Английский

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A chemoselective and one‐pot method for the synthesis of unsymmetrical secondary amines via coupling reaction of ammonia and aryl(alkyl) halides catalyzed by MNP@IAH@Cu‐IL as a bifunctional nanocatalyst

Applied Organometallic Chemistry, Journal Year: 2024, Volume and Issue: 38(6)

Published: March 29, 2024

Copper, an abundant metal on Earth, has re‐emerged as a suitable alternative to versatile Palladium‐catalyzed C–N coupling. Herein, new recoverable and reusable bifunctional catalyst was synthesized by combining ionic liquid linking Cu(II) the surface of Fe 3 O 4 nanoparticles. New nanocatalyst (MNP@IAH@Cu‐IL) completely characterized using different techniques. Continuing, MNP@IAH@Cu‐IL applied in synthesis primary secondary amines via C(sp 2 )‐N coupling reaction successfully. This worked well anilines derivatives high yields excellent quality. Further, we described novel one‐pot process for unsymmetrical amine from two aryl(alkyl) halides. procedure shows attractive features such 100% atom economy, desired products under base‐free conditions, functional group tolerance, work‐up simplicity, recyclability.

Language: Английский

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