Chemo-, regio-, and stereoselective tetrafunctionalization of fluoroalkynes enables divergent synthesis of 5-7-membered azacycles

Chemical Science, Год журнала: 2024, Номер 15(30), С. 12026 - 12035

Опубликована: Янв. 1, 2024

A 1,2,3,4-tetrafunctionalization of polyfluoroalkynes for the divergent construction 5-7-membered ( E )-1,2-difluorovinyl azacycles is developed.

Язык: Английский

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Desymmetrization–Addition Reaction of Cyclopropenes to Imines via Synergistic Photoredox and Cobalt Catalysis

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(28), С. 18892 - 18898

Опубликована: Июль 5, 2024

Herein, we designed a reaction for the desymmetrization-addition of cyclopropenes to imines by leveraging synergy between photoredox and asymmetric cobalt catalysis. This protocol facilitated synthesis series chiral functionalized cyclopropanes with high yield, enantioselectivity, diastereoselectivity (44 examples, up 93% yield >99% ee). A possible mechanism involving cyclopropene desymmetrization Co-H species imine addition Co-alkyl was proposed. study provides novel route important extends frontier metallaphotoredox

Язык: 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, Год журнала: 2024, Номер 63(25)

Опубликована: Янв. 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.

Язык: Английский

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Cobalt-Catalyzed Asymmetric Reductive Alkenylation and Arylation of Heterobiaryl Tosylates: Kinetic Resolution or Dynamic Kinetic Resolution?

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(49), С. 26747 - 26755

Опубликована: Ноя. 29, 2023

Herein, we report a cobalt-catalyzed atroposelective reductive cross-coupling of racemic heterobiaryl tosylates with C(sp2)–X type electrophile. Both aryl and alkenyl halides are competent precursors for this reaction, providing variety heterobiaryls as the products in highly enantioselective manner high functionality tolerance. The related asymmetric arylation alkenylation discovered to proceed divergent mechanisms. reaction pathway changes from kinetic resolution (KR) when bromides iodides bearing strong electron-withdrawing substitution on para-position employed starting materials an enantioconvergent transformation via dynamic KR configurationally labile cobaltacycles relatively electron-rich used. change mechanisms turns out arise relative rates two competing elementary steps, which epimerization cyclic Co(I) intermediates their trapping by coupling electrophiles C(sp2)-type oxidative addition.

Язык: Английский

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CoH-catalyzed asymmetric remote hydroalkylation of heterocyclic alkenes: a rapid approach to chiral five-membered S- and O-heterocycles

Chemical Science, Год журнала: 2024, Номер 15(23), С. 8888 - 8895

Опубликована: Янв. 1, 2024

A highly efficient method achieves precise construction of alkyl chiral centers at remote C3-positions in five-membered S/O-heterocycles via cobalt-catalyzed asymmetric hydroalkylation heterocyclic alkenes.

Язык: Английский

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Cobalt-Catalyzed Enantioselective Reductive Arylation, Heteroarylation, and Alkenylation of Michael Acceptors via an Elementary Mechanism of 1,4-Addition

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(29), С. 20477 - 20493

Опубликована: Июль 10, 2024

Cobalt complexes with chiral quinox ligands effectively promote the enantioselective conjugate addition of enones using aryl, heteroaryl, and alkenyl halides sulfonates. Additionally, a cobalt complex strongly donating diphosphine, BenzP*, successfully catalyzes asymmetric reductive arylation alkenylation α,β-unsaturated amides. Both catalytic systems show broad scopes tolerance sensitive functional groups. reactions can be scaled up low loadings catalysts. Experimental results density theory (DFT) calculations suggest new mechanism elementary 1,4-addition aryl cobalt(I) complexes.

Язык: Английский

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A General Enantioselective α-Alkyl Amino Acid Derivatives Synthesis Enabled by Cobalt-Catalyzed Reductive Addition

Journal of the American Chemical Society, Год журнала: 2024, Номер unknown

Опубликована: Сен. 12, 2024

Enantioenriched unnatural amino acids represent a prevalent motif in organic chemistry, with profound applications biochemistry, medicinal and materials science. Herein, we report cobalt-catalyzed aza-Barbier reaction of dehydroglycines unactivated alkyl halides to afford α-amino esters high enantioselectivity. This catalytic reductive alkylative addition protocol circumvents the use moisture-, air-sensitive organometallic reagents, stoichiometric chiral auxiliaries, enabling conversion variety primary, secondary, even tertiary α-alkyl-amino under mild conditions, thus leading broad functional group tolerance. The expedient access biologically active motifs demonstrates practicality this by reducing number synthetic steps enhancing efficiency.

Язык: Английский

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Catalytic Asymmetric Barbier Reaction of Ketones with Unactivated Alkyl Electrophiles

Journal of the American Chemical Society, Год журнала: 2024, Номер unknown

Опубликована: Окт. 3, 2024

The Barbier reaction is a reductive-type addition of an aldehyde or ketone with organic electrophile in the presence terminal metal reductant, providing straightforward and efficient method for carbon-carbon bond formation. This possesses advantage circumventing preparation moisture- air-sensitive organometallic reagents. However, catalytic ketones to construct tetrasubstituted stereogenic centers largely underdeveloped, despite its great potential accessing synthetically challenging chiral tertiary alcohol. Particularly, leveraging unactivated alkyl electrophiles as coupling components still rarely exploited. Herein, we disclose photoredox-assisted cobalt-catalyzed asymmetric alkylative Barbier-type address aforementioned challenges, thereby allowing construction highly congested carbon centers. fragments could be either readily accessible halides redox-active esters generated through decarboxylative pathway. Both types include primary, secondary, ones, thus affording diverse enantioenriched alcohols broad substrate scope. enantioselective protocol applied expedient synthesis core structure

Язык: Английский

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Cobalt-Catalyzed Chemoselective π–σ–π-Type Tandem Reductive Coupling to Access Isoquinolines via Carbocobaltation of Nitriles

ACS Catalysis, Год журнала: 2025, Номер 15(3), С. 1596 - 1606

Опубликована: Янв. 14, 2025

Transition metal-catalyzed reductive coupling chemistry has been recognized as a powerful tool for the synthesis of diverse organic molecules. However, despite enormous progress in this field, there is no precedent tandem widely accessible nitriles with electrophiles that contain σ- and π-type (σ/π-type) electrophilic functional groups simultaneously. Herein, we have established unique cobalt catalysis system, enabling chemoselective coupling/tandem cyclization reaction aryl halides (Br, Cl, I) bearing carbonyl moiety variety aryl, alkenyl, alkyl via carbocobaltation unknown yet. The protocol allows modular structurally isoquinolines wide substrate scope (>60 examples), good functionalities tolerance, chemoselectivity.

Язык: Английский

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Enantioselective Heck/Tsuji−Trost reaction of flexible vinylic halides with 1,3-dienes

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Янв. 22, 2025

Abstract The enantioselective domino Heck/cross-coupling has emerged as a powerful tool in modern chemical synthesis for decades. Despite significant progress relative rigid skeleton substrates, the implementation of asymmetric cascades highly flexible haloalkene substrates remains challenging and long-standing goal. Here we report an efficient Heck/Tsuji−Trost reaction vinylic halides with 1,3-dienes enabled by palladium catalysis. Specifically, Heck insertion stereodetermining step to form ƞ 3 allyl complex situ trapping nucleophiles enable Heck/etherification formal (4 + 2) cycloaddition manner. Engineering Sadphos bearing androgynous non-C 2 -symmetric chiral sulfinamide phosphine ligands are vital component achieving excellent catalytic reactivity enantioselectivity. This strategy offers general, modular divergent platform rapidly upgrading feedstock dienes various value-added molecules is expected inspire development other Heck/cross-couplings.

Язык: Английский

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