Switchable Divergent Synthesis Using Photocatalysis

ACS Catalysis, Год журнала: 2022, Номер 12(3), С. 1857 - 1878

Опубликована: Янв. 20, 2022

A highly selective and divergent synthesis enables access to various molecules has garnered broad interest from not only organic chemists but also medicinal biologists who work with chemical libraries. Since the 20th century, such transformations have been achieved using transition-metal-catalyzed reactions, in which choice of catalyst or ligand crucially affects selectivity. Over past several decades, photocatalysts attracted a considerable amount attention because they provide additional ways control reaction intermediates product selectivity via electron energy transfer. From this perspective, we highlight recent development switchable syntheses photocatalysts, are difficult achieve classical catalytic transformations.

Язык: Английский

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Accessing chiral sulfones bearing quaternary carbon stereocenters via photoinduced radical sulfur dioxide insertion and Truce–Smiles rearrangement

Nature Communications, Год журнала: 2022, Номер 13(1)

Опубликована: Ноя. 18, 2022

Abstract From the viewpoint of synthetic accessibility and functional group compatibility, photoredox-catalyzed sulfur dioxide insertion strategy enables in situ generation functionalized sulfonyl radicals from easily accessible starting materials under mild conditions, thereby conferring broader application potential. Here we present two complementary photoinduced systems to trigger radical asymmetric Truce–Smiles rearrangements for preparing a variety chiral sulfones that bear quaternary carbon stereocenter. This protocol features broad substrate scope excellent stereospecificity. Aside scalability, introduction stereocenter at position β bioactive molecule-derived further demonstrates practicality potential this methodology.

Язык: Английский

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Recent advances in N-heterocyclic carbene (NHC)-catalyzed fluorination and fluoroalkylation

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(7), С. 2112 - 2133

Опубликована: Янв. 1, 2024

Organofluorine compounds are of high value. NHC-catalyzed fluorination and fluoroalkylation have served as powerful versatile vehicles for accessing the related organofluorines. This review focuses on recent developments in this area.

Язык: Английский

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Strain-release transformations of bicyclo[1.1.0]butanes and [1.1.1]propellanes

Tetrahedron Chem, Год журнала: 2024, Номер 9, С. 100070 - 100070

Опубликована: Фев. 28, 2024

Bicyclo[1.1.0]butanes (BCBs) and [1.1.1]propellanes (tricyclo[1.1.1.01,3]pentanes, TCPs) are structurally unique compounds with different chemical properties. Strain-release driven reactions have emerged as an atom- step-economic strategy for the organic synthesis. Using this strategy, a variety of functional ring molecules been efficiently synthesized, including various cyclobutane molecules, bicyclo[2.1.1]hexanes, bicyclo[1.1.1]pentanes, others. More specifically, these strain release-driven include aspects nucleophilic addition, radical electrophilic or transition metal catalysis. This review will discuss recent developments in strain-release transformations bicyclo[1.1.0]butanes [1.1.1]propellanes.

Язык: Английский

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γ-Amino Alcohols via Energy Transfer Enabled Brook Rearrangement

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(15), С. 10899 - 10907

Опубликована: Апрель 3, 2024

In the long-standing quest to synthesize fundamental building blocks with key functional group motifs, photochemistry in recent past has comprehensively established its attractiveness. Amino alcohols are not only functionally diverse but ubiquitous biologically active realm of compounds. We developed bench-stable bifunctional reagents that could then access sparsely reported γ-amino directly from feedstock alkenes through energy transfer (EnT) photocatalysis. A designed 1,3-linkage across is made possible by intervention a radical Brook rearrangement takes place downstream EnT-mediated homolysis our reagent(s). combination experimental mechanistic investigations and detailed computational studies (DFT) indicates chain propagated reaction pathway.

Язык: Английский

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Radical 1,2-Nitrogen Migration Cascades of β-Bromo α-Amino Acid Esters to Access β-Amino Acid Motifs Enabled by Cooperative Ni/Diboron Catalysis

ACS Catalysis, Год журнала: 2024, Номер 14(8), С. 5491 - 5502

Опубликована: Март 28, 2024

Amino acid esters serve as crucial intermediates in protein synthesis and common structural elements biologically active natural compounds. Herein, we present an efficient radical cascade reaction involving 1,2-nitrogen migration C(sp2)–H intramolecular cyclization, enabling access to a diverse array of β-amino motifs. Upon cooperative Ni/diboron catalysis, π-system-independent 1,2-N-shift β-bromo α-amino is achieved, which allows the formation two new bonds, including C(sp3)–C(sp2) bond C(sp3)–N bond. The exhibits extensive substrate compatibility high diastereoselectivity proceeds without need for oxidants, toxic initiators, and/or elevated temperatures. It has been observed that diboron compounds both activating reagent inert C–N cleavage/migration reductant Ni catalytic cycle. This sheds light on remote N-functionalities π-systems. cascades followed by intermolecular halogenation or selenation are also demonstrated.

Язык: Английский

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Di-π-ethane Rearrangement of Cyano Groups via Energy-Transfer Catalysis

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(27), С. 18210 - 18217

Опубликована: Май 24, 2024

Molecular rearrangement occupies a pivotal position among fundamental transformations in synthetic chemistry. Radical translocation has emerged as prevalent tool, efficiently facilitating the migration of diverse functional groups. In contrast, development di-π-methane remains limited, particularly terms cyano This is primarily attributed to energetically unfavorable three-membered-ring transition state. Herein, we introduce an unprecedented di-π-ethane enabled by energy-transfer catalysis under visible light conditions. innovative open-shell boasts broad tolerance toward range groups, encompassing even complex drug and natural product derivatives. Overall, reported represents complementary strategy radical catalysis.

Язык: Английский

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Radical Brook rearrangement: past, present, and future

Chemical Society Reviews, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

This review aims to provide an overview of radical Brook rearrangement, which is organized by grouping three type reactive species generated via the unique rearrangement process.

Язык: Английский

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Biomimetic 1,2-amino migration via photoredox catalysis

Nature Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Март 7, 2025

Synthetic organic chemists continually draw inspiration from biocatalytic processes to innovate synthetic methodologies beyond existing catalytic platforms. Within this context, although 1,2-amino migration represents a viable biochemical process, it remains underutilized within the chemistry community. Here we present biomimetic accomplished through synergistic combination of mechanism and photoredox catalysis. This platform enables modular synthesis γ-substituted β-amino acids by utilizing abundant α-amino-acid derivatives readily available molecules as coupling partners. mild method features excellent substrate functionality compatibility, affording diverse range (more than 80 examples) without need for laborious multistep synthesis. Mechanistic studies, supported both experimental observations theoretical analysis, indicate that involves radical addition α-vinyl-aldimine ester, 3-exo-trig cyclization subsequent rearrangement process. We anticipate transformation will serve versatile highly efficient construction unnatural acids. Enzyme-catalysed process is currently Building upon mechanism, photoredox-catalysed has been developed. By integrating conditions, approach library

Язык: Английский

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Switchable 1,2-Rearrangement Enables Expedient Synthesis of Structurally Diverse Fluorine-Containing Scaffolds

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(26), С. 11626 - 11637

Опубликована: Май 23, 2022

Skeletal rearrangement that changes the connectivity of molecule via cleavage and reorganization carbon–carbon bonds is a fundamental powerful strategy in complex molecular assembly. Because lack effective methods to control migratory tendency different groups, achieving switchable selectivity skeletal has been long-standing quest. Metal-based dyotropic provides unique opportunity address this challenge. However, remains unexplored. Herein, we show such problem could be solved by modifying ligands on metal catalyst changing oxidation states aptitude thereby providing ligand-controlled, strategy. Experimental density functional theory calculation studies prove rational design. The occurs only when nickel(II) intermediate reduced more nucleophilic nickel(I) species, sterically hindered iPrPDI ligand facilitates 1,2-aryl/Ni rearrangement, while terpyridine promotes 1,2-acyl/Ni rearrangement. This method allows site-selective activation C–C applied for divergent synthesis four medicinally relevant fluorine-containing scaffolds from same starting material.

Язык: Английский

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