Copper-Catalyzed Selective Electron Transfer Enables Switchable Divergent Synthesis of 3-Functionalized Oxindoles

ACS Catalysis, Год журнала: 2023, Номер 13(5), С. 3085 - 3092

Опубликована: Фев. 16, 2023

Oxidative rearrangement of 3-substituted indoles is a fundamental organic transformation for the synthesis 2-oxindole scaffolds. However, this time-consuming and complex task produces single type product via two-electron oxidation using stoichiometric chemical oxidants. Herein, we report unified efficient copper-catalyzed selective single-electron transfer strategy three reactions air (O2) as terminal oxidant, providing streamlined practical synthetic approach to access 3-hydroxyl-, 3-alkoxyl-, 3-hygrogenous-2-oxindoles 3-radical-2-hydroxyl indoline intermediate. This copper catalysis protocol demonstrates high chemoselectivity, good functional group tolerance, broad application potential in modular biologically 3-functionalized oxindole derivatives.

Язык: Английский

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Cobalt‐Catalyzed Asymmetric Aza‐Nozaki–Hiyama–Kishi (NHK) Reaction of α‐Imino Esters with Alkenyl Halides

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(7)

Опубликована: Янв. 2, 2024

Chromium-catalyzed enantioselective Nozaki-Hiyama-Kishi (NHK) reaction represents one of the most powerful approaches for formation chiral carbon-heteroatom bond. However, construction sterically encumbered tetrasubstituted stereocenter through NHK still posts a significant challenge. Herein, we disclose cobalt-catalyzed aza-NHK ketimine with alkenyl halide to provide convenient synthetic approach manufacture enantioenriched α-vinylic amino acid. This protocol exhibits excellent functional group tolerance 99 % ee in cases. Additionally, this asymmetric reductive method is also applicable aldimine access trisubstituted stereogenic centers.

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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Copper-Catalyzed Asymmetric Deconstructive Alkynylation of Cyclic Oximes

ACS Catalysis, Год журнала: 2021, Номер 11(10), С. 6010 - 6019

Опубликована: Май 3, 2021

A general asymmetric deconstructive alkynylation of cyclic oximes with terminal alkynes was reported using copper/chiral cinchona alkaloid-based N,N,P-ligand catalysts and used to produce more than 60 examples enantioenriched γ- δ-alkynyl nitriles in a highly functional group-compatible manner. wide variety low-cost easily available substituent diversity were found be well tolerated the current transformation good group tolerance. The resulting chiral alkynyl are intermediates, which could converted into skeletally diverse molecules, including amides, ε-alkenyl carbamate, ζ-keto nitrile, under suitable reaction conditions.

Язык: Английский

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Cobalt‐Catalyzed Enantioselective Alkenylation of Aldehydes

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(33)

Опубликована: Май 31, 2024

Catalytic enantioselective alkenylation of aldehydes with easily accessible alkenyl halides promoted by a chiral cobalt complex derived from newly developed tridentate bisoxazolinephosphine is presented. Such processes represent an unprecedented reaction pathway for catalysis and general approach that enable rapid construction highly diversified enantioenriched allylic alcohols containing 1,1-, 1,2-disubstituted trisubstituted alkene as well axial stereogenicity in up to 99 % yield : 1 er without the need preformation alkenyl-metal reagents. DFT calculations revealed origin enantioselectivity.

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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Lewis-Acid-Catalyzed Asymmetric Alkynylation of Alkynyl 1,2-Diketones: Controllable Formation of 3(2H)-Furanones and α-Hydroxy Ketones

Organic Letters, Год журнала: 2020, Номер 22(17), С. 6948 - 6953

Опубликована: Авг. 21, 2020

We report the highly regio- and enantioselective alkynylation of alkynyl 1,2-diketones under Lewis acid catalysis, leading to formation a series biologically important 3(2H)-furanones with high excellent ee values. Moreover, slight change reaction conditions produces range functionalized α-hydroxy ketones level enantioselectivity. A variety further transformations can be easily achieved, demonstrating synthetic potential this protocol.

Язык: Английский

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Reversal of Enantioselectivity in the Copper-Aminophenol Sulfonamide Catalyzed Alkynylation of Isatins by Slightly Tuning the Ligand Structure and Basic Additives

Organic Letters, Год журнала: 2021, Номер 23(15), С. 5739 - 5743

Опубликована: Июль 19, 2021

A series of new chiral aminophenol sulfonamide ligands with a monochiral arm has been developed for the first Cu(I) catalyzed enantiodivergent alkynylation isatins. Dramatic reversal enantioselectivity was accomplished by slightly tuning substituted benzenesulfonamide and achiral basic additives. wide range both terminal alkynes isatins are tolerated this catalyst system up to 99% yield 97% ee.

Язык: Английский

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Cobalt‐Catalyzed Asymmetric Aza‐Nozaki–Hiyama–Kishi (NHK) Reaction of α‐Imino Esters with Alkenyl Halides

Angewandte Chemie, Год журнала: 2024, Номер 136(7)

Опубликована: Янв. 2, 2024

Abstract Chromium‐catalyzed enantioselective Nozaki–Hiyama–Kishi (NHK) reaction represents one of the most powerful approaches for formation chiral carbon‐heteroatom bond. However, construction sterically encumbered tetrasubstituted stereocenter through NHK still posts a significant challenge. Herein, we disclose cobalt‐catalyzed aza‐NHK ketimine with alkenyl halide to provide convenient synthetic approach manufacture enantioenriched α‐vinylic amino acid. This protocol exhibits excellent functional group tolerance 99 % ee in cases. Additionally, this asymmetric reductive method is also applicable aldimine access trisubstituted stereogenic centers.

Язык: Английский

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Highly asymmetric aldol reaction of isatins and ketones catalyzed by chiral bifunctional primary-amine organocatalyst on water

Organic & Biomolecular Chemistry, Год журнала: 2023, Номер 21(43), С. 8695 - 8701

Опубликована: Янв. 1, 2023

Herein, we have reported an environmentally friendly asymmetric aldol reaction between isatins and ketones catalyzed by double-hydrogen-bonded primary amine organocatalysts on water under mild conditions. Enantioenriched 3-hydroxy-2-oxindoles were obtained in high yields (up to 99%) excellent stereoselectivities 99 : 1 dr 99% ee) optimal Furthermore, the model involving isatin cyclohexanone was successfully scaled 10 mmol with no reduction yield or stereoselectivity. In addition, catalyst recovered via simple filtration subsequently reused water, which highlights its good application potential.

Язык: Английский

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