Cobalt-catalyzed enantioselective C–H/N–H annulation of aryl sulfonamides with allenes or alkynes: facile access to C–N axially chiral sultams

Chemical Science, Год журнала: 2023, Номер 14(26), С. 7291 - 7303

Опубликована: Янв. 1, 2023

Herein we report a cobalt-catalyzed enantioselective C-H/N-H annulation of aryl sulfonamides with allenes and alkynes, using either chemical or electrochemical oxidation. By O2 as the oxidant, proceeds efficiently low catalyst/ligand loading 5 mol% tolerates wide range allenes, including 2,3-butadienoate, allenylphosphonate, phenylallene, resulting in C-N axially chiral sultams high enantio-, regio-, position selectivities. The alkynes also exhibits excellent enantiocontrol (up to >99% ee) variety functional sulfonamides, internal terminal alkynes. Furthermore, oxidative is achieved simple undivided cell, demonstrating versatility robustness cobalt/Salox system. gram-scale synthesis asymmetric catalysis further highlight practical utility this method.

Язык: Английский

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Synthesis of Axially Chiral Biaryls through Cobalt(II)‐Catalyzed Atroposelective C−H Arylation

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(40)

Опубликована: Авг. 16, 2023

Highly efficient synthesis of axially chiral biaryl amines through cobalt-catalyzed atroposelective C-H arylation using easily accessible cobalt(II) salt and salicyloxazoline ligand has been reported. This methodology provides a straightforward sustainable access to broad range enantioenriched biaryl-2-amines in good yields (up 99 %) with excellent enantioselectivities % ee). The synthetic utility the unprecedented method is highlighted by its scalability diverse transformations.

Язык: Английский

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N,O-Auxiliary Enabled Cobaltaelectro-Catalyzed Atroposelective C–H Annulation

ACS Catalysis, Год журнала: 2023, Номер 14(1), С. 1 - 9

Опубликована: Дек. 7, 2023

Herein, we disclosed an efficient synthesis of C–N axially chiral pyridine-N-oxides through cobalt-catalyzed enantioselective C–H activation and annulation under electro-oxidative conditions. This protocol is accomplished by using a readily available cobalt(II) catalyst salicyloxazoline (Salox) ligand in undivided cell. The combination electrochemical simple Co/Salox system enabled effective control over the chemo- enantioselectivity process. A broad range benzamides alkynes bearing diverse functional groups are well compatible to deliver products with high yields enantioselectivities (up 97% yield 99% ee). scalability, asymmetric application, transformations demonstrated synthetic practicality. Moreover, photoluminescence properties further highlight potential applications this strategy material development performance enhancement.

Язык: Английский

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Unlocking the Potential of Oxidative Asymmetric Catalysis with Continuous Flow Electrochemistry

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(11), С. 7178 - 7184

Опубликована: Март 11, 2024

In the field of catalytic asymmetric synthesis, less-treated path lies in oxidative transformations. The hurdles pinpointing appropriate chemical oxidants and addressing their compatibility issues with catalysts functionalities present significant challenges. Organic electrochemistry, employing traceless electrons for redox reactions, is underscored as a promising solution. However, commonly used electrolysis batch cells introduces its own set challenges, hindering advancement electrochemical catalysis. Here we introduce microfluidic electrochemistry platform single-pass continuous flow reactors that exhibits wide-ranging applicability to various This exemplified through sulfenylation 1,3-dicarbonyls, dehydrogenative C–C coupling, alkene annulation processes. unique properties not only eliminate need but also enhance reaction efficiency reduce use additives electrolytes. These salient features expedite discovery development addition, production facilitated by parallel ensures straightforward upscaling, removing necessity reoptimization across scales, evidenced direct translation from milligram screening hectogram synthesis.

Язык: Английский

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Copper/BINOL-Catalyzed Enantioselective C–H Functionalization toward Planar Chiral Ferrocenes Under Mild Conditions

ACS Catalysis, Год журнала: 2024, Номер 14(6), С. 4030 - 4039

Опубликована: Фев. 28, 2024

Copper-catalyzed enantioselective C–H activation proceeding through an inner-sphere mechanism remains a huge challenge. Herein, copper-catalyzed alkynylation with terminal alkynes assisted by 8-aminoquinoline using readily available (S)-BINOL as the chiral ligand was disclosed. The reaction proceeded under mild conditions catalytic amount of copper salt, providing range ferrocenes in good yields and enantioselectivities (0 °C, up to 77% yield 94% ee). alteration stoichiometric chemical oxidant renewable electricity is also feasible at ambient temperature, demonstrating robustness this copper/BINOL catalysis. Notably, first cupraelectrocatalyzed reaction. Gram-scale synthesis, versatile transformations, application resulting oxazoline–olefin asymmetric synthesis highlight utility protocols.

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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Enantioselective C–H bond functionalization under Co(iii)-catalysis

Chemical Communications, Год журнала: 2024, Номер 60(25), С. 3354 - 3369

Опубликована: Янв. 1, 2024

Enantioselective C–H functionalization relies on 4d and 5d metals, but with their depletion, sustainable alternatives using 3d metals are crucial.

Язык: Английский

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Cobaltaelectro‐Catalyzed C–H Activation for Central and Axial Double Enantio‐Induction

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(31)

Опубликована: Май 17, 2024

In recent years, enantioselective electrocatalysis has surfaced as an increasingly-effective platform for sustainable molecular synthesis. Despite indisputable progress, strategies that allow the control of two distinct stereogenic elements with high selectivity remain elusive. contrast, we, herein, describe electrochemical cobalt-catalyzed C-H activations enable installation chiral centers along a axis levels enantio- and diastereoselectivities. The developed strategy allowed C-H/N-H activations/annulations cyclic non-cyclic alkenes providing expedient access to various central well atropo-chiral dihydroisoquinolinones paired valuable hydrogen evolution reaction. Studies on atropo-stability obtained compounds demonstrated exceedingly mild conditions ensured by electrocatalytic process were key achieved stereoselectivities.

Язык: Английский

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Copper-Mediated Enantioselective C–H Thiolation of Ferrocenes Enabled by the BINOL Ligand

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Янв. 30, 2025

Transition-metal-catalyzed enantioselective C-H activation has transformed the landscape of asymmetric synthesis, enabling efficient conversion bonds into C-C and carbon-heteroatom (C-X) bonds. However, formation C-S through thiolation remains underdeveloped due to challenges such as catalyst deactivation competitive coordination sulfur-containing compounds with chiral ligands. Herein, we report an unprecedented approach constructing sulfur-substituted planar ferrocenes (PCFs) copper-mediated enabled by only a 2.5 mol % 1,1'-bi-2,2'-naphthol (BINOL) ligand. A variety PCFs were obtained in good yields (up 83%) excellent enantioselectivity >99% ee). Mechanistic studies reveal that irreversible serves both stereo- rate-determining step can be achieved catalytic amounts Cu species. Furthermore, utility this protocol is illustrated gram-scale removal directing group, synthesis N,S-chiral ligands well rotaxanes. This significant advancement not expands tool kit for organosulfur but also highlights potential synthesis.

Язык: Английский

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Parametrization of κ²-N,O-Oxazoline Preligands for Enantioselective Cobaltaelectro-Catalyzed C–H Activations

ACS Catalysis, Год журнала: 2025, Номер unknown, С. 4450 - 4459

Опубликована: Фев. 28, 2025

Enantioselective electrocatalyzed C–H activations have emerged as a transformative platform for the assembly of value-added chiral organic molecules. Despite recent progress, construction multiple C(sp3)-stereogenic centers via C(sp3)–C(sp3) bond formation has thus far proven to be elusive. In contrast, we herein report an annulative activation strategy, generating Fsp3-rich molecules with high levels diastereo- and enantioselectivity. κ2-N,O-oxazoline preligands were effectively employed in enantioselective cobalt(III)-catalyzed reactions. Using DFT-derived descriptors regression statistical modeling, performed parametrization study on modularity preligands. The resulted model describing ligands' selectivity characterized by key steric, electronic, interaction behaviors.

Язык: Английский

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