Metalloradical Catalysis: General Approach for Controlling Reactivity and Selectivity of Homolytic Radical Reactions

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(20)

Published: March 13, 2024

Abstract Since Friedrich Wöhler's groundbreaking synthesis of urea in 1828, organic over the past two centuries has predominantly relied on exploration and utilization chemical reactions rooted two‐electron heterolytic ionic chemistry. While one‐electron homolytic radical chemistry is both rich fundamental reactivities attractive with practical advantages, synthetic application been long hampered by formidable challenges associated control reactivity selectivity high‐energy intermediates. To fully harness untapped potential for synthesis, there a pressing need to formulate radically different concepts broadly applicable strategies address these outstanding issues. In pursuit this objective, researchers have actively developing metalloradical catalysis (MRC) as comprehensive framework guide design general approaches controlling stereoselectivity reactions. Essentially, MRC exploits metal‐centered radicals present open‐shell metal complexes catalysts activation substrates generate metal‐entangled key intermediates govern reaction pathway stereochemical course subsequent catalytic processes. Different from conventional transition complexes, operates through utilizing stepwise mechanisms.

Language: Английский

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Alkene Hydrobenzylation by a Single Catalyst That Mediates Iterative Outer-Sphere Steps

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(4), P. 2351 - 2357

Published: Jan. 17, 2024

Cross-coupling catalysts typically react and unite functionally distinct partners via sequential inner-sphere elementary steps: coordination, migratory insertion, reductive elimination, etc. Here, we report a single catalyst that cross-couples styrenes benzyl bromides iterative outer-sphere metal–ligand-carbon interactions. Each partner forms stabilized radical intermediate, yet heterocoupled products predominate. The system is redox-neutral and, thus, avoids exogenous oxidants, resulting in simple scalable conditions. Numerous variations of alkene hydrobenzylation are made possible, including access to the privileged heterodibenzyl (1,2-diarylethane) motif challenging quaternary carbon variants.

Language: Английский

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Cobalt‐Catalyzed Enantioselective Reductive α‐Chloro‐Carbonyl Addition of Ketimine to Construct the β‐Tertiary Amino Acid Analogues

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(25)

Published: Jan. 22, 2024

β-Tertiary amino acid derivatives constitute one of the most frequently occurring units in natural products and bioactive molecules. However, efficient asymmetric synthesis this motif still remains a significant challenge. Herein, we disclose cobalt-catalyzed enantioselective reductive addition reaction ketimine using α-chloro carbonyl compound as radical precursor, providing expedient access to diverse array enantioenriched β-quaternary analogues. This protocol exhibits outstanding enantioselectivity broad substrate scope with excellent functional group tolerance. Preliminary mechanism studies rule out possibility Reformatsky-type confirm involvement species stereoselective process. The synthetic utility has been demonstrated through rapid assembly iterative oligopeptide, showcasing its versatile platform for late-stage modification drug candidates.

Language: Английский

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Stereoselective gem-Difunctionalization of Diazo Compounds with Vinyl Sulfoxonium Ylides and Thiols via Metalloradical Catalysis

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(4), P. 2805 - 2815

Published: Feb. 8, 2024

Multicomponent reactions that involve carbenes with nucleophiles and electrophiles have demonstrated broad applications in synthetic chemistry. However, because of the high reactivity transient carbenes, involving two carbene precursors nucleophile presence a metal catalyst remain unexplored. Herein, three-component stereoselective gem-difunctionalization diazo compounds thiols vinyl sulfoxonium ylide is disclosed via Co(II)-based metalloradical catalysis. The key aspect present strategy to exploit intrinsic difference ylides thiol catalysts. Doyle–Kirmse rearrangement sulfonium involves convergent assembly situ-generated intermediates, such as allyl sulfide α- metalloalkyl radical complex, provide expeditious access tertiary scaffolds. Combined experimental quantum chemical calculations unveil intricate mechanism this reaction. Furthermore, theoretical studies on noncovalent interactions selectivity-determining transition states explain origin experimentally obtained diastereoselectivity.

Language: Английский

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Asymmetric Intramolecular Amination Catalyzed with Cp*Ir-SPDO via Nitrene Transfer for Synthesis of Spiro-Quaternary Indolinone

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(28), P. 18841 - 18847

Published: July 8, 2024

An asymmetric intramolecular spiro-amination to high steric hindering

Language: Английский

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Design and Synthesis of C₄‐Symmetric Axially Chiral β‐Aryl Porphyrins and Application for Supporting Ir(III)‐Catalyzed Enantioselective C−H Alkylation

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(28)

Published: April 29, 2024

A hitherto unknown class of C

Language: Английский

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Who is Who in the Carbene Chemistry of N‐Sulfonyl Hydrazones

Chinese Journal of Chemistry, Journal Year: 2024, Volume and Issue: 42(17), P. 2071 - 2108

Published: May 27, 2024

Comprehensive Summary Over the past few decades, N ‐sulfonyl hydrazones have been recognized as alternative precursors for hazardous diazo compounds in organic synthesis, allowing diverse innovative and original chemical transformations that were otherwise difficult to achieve. This critical review summarizes major advancements carbene chemistry of hydrazones. The contents this are organized based on research conducted by leading scientists who made significant contributions field. individual transfer reactions their mechanisms, well potential applications synthesis natural products complex bioactive molecules, thoroughly discussed.

Language: Английский

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Reaction Discovery Using Spectroscopic Insights from an Enzymatic C–H Amination Intermediate

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(30), P. 20556 - 20562

Published: July 22, 2024

Engineered hemoproteins can selectively incorporate nitrogen from nitrene precursors like hydroxylamine,

Language: Английский

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Highly diastereoselective and enantioselective cyclopropanation of alkenes catalyzed by a chiral iridium(III) porphyrin complex

Chem Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 101262 - 101262

Published: Feb. 1, 2025

Language: Английский

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Gold-Catalyzed Cascade Cycloisomerization of 3-Allyloxy-1,6-diynes to Cyclopropyl- and Cyclobutyl-Fused Benzofurans and Chromen-3a(1H)-ols

Organic Letters, Journal Year: 2024, Volume and Issue: 26(13), P. 2635 - 2640

Published: March 25, 2024

A synthetic method for the efficient preparation of partially hydrogenated benzo[f]cyclobuta[cd]cyclopenta[h]benzofurans and cyclopropa[c]chromen-3a(1H)-ols that relies on gold(I)-catalyzed cascade cycloisomerization 3-allyloxy-1,6-diynes is described.

Language: Английский

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