N–O Bond Activation by Energy Transfer Photocatalysis

Accounts of Chemical Research, Год журнала: 2022, Номер 55(17), С. 2526 - 2541

Опубликована: Авг. 20, 2022

ConspectusA radical shift toward energy transfer photocatalysis from electron under visible-light photoirradiation is often due to the greener prospects of atom and process economy. Recent advances in embrace unique strategies for direct small-molecule activation sometimes extraordinary chemical bond formation absence additional/sacrificial reagents. Selective requires careful selection substrates photocatalysts a perfect match with respect their triplet energies while having incompatible redox potentials prevent competitive pathways. Substrates containing labile N–O bonds are potential targets generating reactive key intermediates via access variety functionalized molecules. Typically, differential densities N O heteroatoms have been exploited generation either N- or O-centered by pathway. However, latest developments involve homolysis generate both radicals subsequent utilization diverse organic transformations, also sacrificial In this Account, we highlight our contributions field intermediates, coverage useful mechanistic insights. More specifically, well-designed bond-containing such as 1,2,4-oxadiazolines, oxime esters, N-indolyl carbonates, N-enoxybenzotriazoles were successfully utilized versatile transformations involving selective over high state energy. Direct N-, O-, C-centered (if decarboxylation follows) was achieved cross-couplings rearrangement processes. particular, open-shell nitrogen including N(sp2) N(sp3) nitrenes, utilized. Notably, diversified identical through control reaction conditions. 1,2,4-Oxadiazolines converted into spiro-azolactams iminyl presence 1O2, benzimidazoles, sulfoximines external sulfoxide reagent nitrene inert Besides, esters underwent intramolecular C(sp3)–N radical–radical coupling intermolecular combined transfer–hydrogen strategy. Furthermore, series electrochemical photophysical experiments well computational studies performed substantiate proposed energy-transfer-driven We hope that Account will serve guide rational design processes further bonds.

Язык: Английский

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Catalytic Asymmetric Synthesis of Atropisomers Bearing Multiple Chiral Elements: An Emerging Field

Angewandte Chemie International Edition, Год журнала: 2023, Номер 63(3)

Опубликована: Ноя. 2, 2023

With the rapid development of asymmetric catalysis, demand for enantioselective synthesis complex and diverse molecules with different chiral elements is increasing. Owing to unique features atropisomerism, catalytic atropisomers has attracted a considerable interest from chemical science community. In particular, introducing additional elements, such as carbon centered chirality, heteroatomic planar helical into provides an opportunity incorporate new properties axially compounds, thus expanding potential applications atropisomers. Thus, it important perform transformations synthesize bearing multiple elements. spite challenges in transformations, recent years, chemists have devised powerful strategies under organocatalysis or metal synthesizing wide range enantioenriched Therefore, become emerging field. This review summarizes progress this field indicates challenges, thereby promoting horizon.

Язык: Английский

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Photoinduced Cobalt-Catalyzed Desymmetrization of Dialdehydes to Access Axial Chirality

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(12), С. 6944 - 6952

Опубликована: Март 15, 2023

Enantioselective metallaphotoredox catalysis, which combines photoredox catalysis and asymmetric transition-metal has become an effective approach to achieve stereoconvergence under mild conditions. Although many impressive synthetic approaches have been developed access central chirality, the construction of axial chirality by still remains underexplored. Herein, we report two visible light-induced cobalt-catalyzed reductive couplings biaryl dialdehydes synthesize axially chiral aldehydes (60 examples, up 98% yield, >19:1 dr, >99% ee). This protocol shows good functional group tolerance, broad substrate scope, excellent diastereo- enantioselectivity.

Язык: Английский

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Catalytic atroposelective synthesis

Nature Catalysis, Год журнала: 2024, Номер 7(5), С. 483 - 498

Опубликована: Апрель 30, 2024

Язык: Английский

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Atroposelective catalysis

Nature Reviews Chemistry, Год журнала: 2024, Номер 8(7), С. 497 - 517

Опубликована: Июнь 18, 2024

Язык: Английский

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Dynamic Kinetic Reductive Grignard-Type Addition for the Construction of Axial and Central Chirality

ACS Catalysis, Год журнала: 2025, Номер unknown, С. 1147 - 1157

Опубликована: Янв. 3, 2025

This study describes a photoredox/cobalt dual-catalyzed asymmetric Grignard-type addition reaction, enabling the synthesis of axially chiral hexatomic (six–six) N-heterobiaryls bearing extra secondary alcohol unit via an efficient dynamic kinetic transformation racemic N-heterobiaryl triflate substrates. The conversion facilitated both photoredox and classical reductive reaction conditions exhibits good functional group tolerance, broad substrate scope, satisfactory stereoselectivity. Furthermore, control experiments density theory calculations provide preliminary mechanistic insights.

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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Ruthenium(II)/Imidazolidine Carboxylic Acid‐Catalyzed C−H Alkylation for Central and Axial Double Enantio‐Induction

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(47)

Опубликована: Сен. 15, 2022

Enantioselective C-H activation has surfaced as a transformative toolbox for the efficient assembly of chiral molecules. However, despite major advances in rhodium and palladium catalysis, ruthenium(II)-catalyzed enantioselective thus far largely proven elusive. In contrast, we herein report on highly regio-, diastereo- alkylation. The key to success was represented by identification novel C2-symmetric imidazolidine carboxylic acids (CICAs), which are easily accessible one-pot fashion, effective ligands. This ruthenium/CICA system enabled installation central axial chirality, featured excellent branched linear ratios with generally >20 : 1 dr up 98 2 er. Mechanistic studies experiment computation were carried out understand catalyst mode action.

Язык: Английский

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Access to chiral β-sulfonyl carbonyl compounds via photoinduced organocatalytic asymmetric radical sulfonylation with sulfur dioxide

Chemical Science, Год журнала: 2022, Номер 13(30), С. 8834 - 8839

Опубликована: Янв. 1, 2022

An organocatalytic enantioselective radical reaction of potassium alkyltrifluoroborates, DABCO·(SO

Язык: Английский

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Strategies That Utilize Ion Pairing Interactions to Exert Selectivity Control in the Functionalization of C–H Bonds

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(40), С. 18195 - 18211

Опубликована: Сен. 30, 2022

Electrostatic attraction between two groups of opposite charge, typically known as ion-pairing, offers unique opportunities for the design systems to enable selectivity control in chemical reactions. Catalysis using noncovalent interactions is an established and vibrant research area, but it noticeable that hydrogen bonding are still main interaction choice system design. Opposite charges experience powerful force Coulombic have ability exert fundamental influence on outcome reactions involve charged reagents, intermediates or catalysts. In this Perspective, we will examine how ion-pairing been used C-H bond functionalization processes. This broad class provides interesting thought-provoking lens through which application strategies because one encompasses great mechanistic diversity, poses significant challenges, perhaps most importantly immense interest synthetic chemists both industry academia. We survey proceed via radical ionic mechanisms alongside those transition metal catalysis deal with site-selectivity enantioselectivity. anticipate emerging area develops, become ever-more important strategy control.

Язык: Английский

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