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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Cobalt-Catalyzed Asymmetric Migratory Nozaki–Hiyama–Kishi Coupling

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

Опубликована: Сен. 16, 2024

Selective functionalization of ubiquitous C-H bonds based on 1,

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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Nickel-Catalyzed Enantioselective Reductive N-Cyclization–Thiolation Reaction of Alkene-Tethered Oxime Esters and Disulfides

Organic Letters, Год журнала: 2024, Номер unknown

Опубликована: Сен. 27, 2024

Asymmetric aza-Heck cyclization and coupling reactions offer efficient access to enantioenriched

Язык: Английский

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Amide and peptide synthesis via nickel-catalyzed cross-electrophile coupling

Cell Reports Physical Science, Год журнала: 2024, Номер unknown, С. 102248 - 102248

Опубликована: Окт. 1, 2024

Язык: Английский

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Transition-metal-catalyzed asymmetric functionalization of simple heterocycles: Facile access to chiral saturated heterocycles

Chem Catalysis, Год журнала: 2023, Номер 4(1), С. 100798 - 100798

Опубликована: Ноя. 7, 2023

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, Год журнала: 2024, Номер 136(25)

Опубликована: Янв. 22, 2024

Abstract 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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Indium-Catalyzed Reductive Coupling Enabled Efficient Synthesis of Acylphosphine Oxides and Diphosphines

ACS Catalysis, Год журнала: 2024, Номер 14(5), С. 3241 - 3247

Опубликована: Фев. 15, 2024

The unique low level of the ionization potential indium(0) to indium(I) makes it an appealing metal for organic synthesis. Here, we present indium-catalyzed reductive cross-coupling between chlorophosphines (R2PCl) or dichlorophosphines (RPCl2) with acyl chlorides (RCOCl). This one-pot approach, using indium-catalysis followed by oxidation, generates a variety mono- bis-acylphosphine oxides in good yields. Additionally, this protocol offers convenient pathway obtain photoinitiators, Luricin TPO and IRGACURE 819, that are widely used industry. Experimental computational studies indicate intermediacy phosphorus-based radical species dimerize diphosphines, which then couple through four-membered transition state. Furthermore, also explore homocoupling R2PCl RPCl2, provides facile access various P–P bond formations.

Язык: Английский

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Cobalt-Catalyzed Enantioselective Reductive Addition of Ketimine with Cyclopropyl Chloride to Construct the Chiral Amino Esters Bearing Cyclopropyl Fragments

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(22), С. 6311 - 6318

Опубликована: Янв. 1, 2024

Co-catalyzed asymmetric reductive addition of ketimine with cyclopropyl chloride has been realized to access diverse chiral amino esters bearing fragments broad functional group tolerance and excellent enantioselectivities.

Язык: Английский

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Expedient and divergent synthesis of unnatural peptides through cobalt-catalyzed diastereoselective umpolung hydrogenation

Science Advances, Год журнала: 2023, Номер 9(51)

Опубликована: Дек. 20, 2023

The development of a reliable method for asymmetric synthesis unnatural peptides is highly desirable and particularly challenging. In this study, we present versatile efficient approach that uses cobalt-catalyzed diastereoselective umpolung hydrogenation to access noncanonical aryl alanine peptides. This protocol demonstrates good tolerance toward various functional groups, amino acid sequences, peptide lengths. Moreover, the versatility reaction illustrated by its successful application in late-stage functionalization formal representative chiral natural products pharmaceutical scaffolds. strategy eliminates need synthesizing alanines before formation, does not result racemization or epimerization. underlying mechanism was extensively explored through deuterium labeling, control experiments, HRMS identification, UV-Vis spectroscopy, which supported reasonable CoI/CoIII catalytic cycle. Notably, acetic methanol serve as safe cost-effective hydrogen sources, while indium powder acts terminal electron source.

Язык: Английский

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