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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Formation of Chiral All-Carbon Quaternary Stereocenters by Photoinduced Cobalt-Catalyzed Enantioselective Radical Coupling

ACS Catalysis, Год журнала: 2024, Номер 14(18), С. 13550 - 13556

Опубликована: Авг. 28, 2024

Photoinduced enantioselective strategies provide an efficient way to access chiral all-carbon quaternary stereocenters. Compared with the well-developed metal-catalyzed asymmetric conjugate addition of organometallic reagents enones, construction stereocenters through a radical process still remains challenging, especially for acyclic enones due their enhanced conformational mobility. Herein, we disclose photoinduced cobalt-catalyzed coupling α,β-unsaturated 2-acyl imidazoles and α-silylamines give β,β-disubstituted γ-amino acid derivatives carbon The facile protocol shows good functional group tolerance broad substrate scope. corresponding products were obtained in generally yields (up 96%) high enantioselectivities 99:1 e.r.).

Язык: Английский

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Chiral Magnesium(II)-Catalyzed Asymmetric Hydroalkylation of Imine-Containing Vinylazaarenes through Conjugate Addition

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Март 29, 2025

The synthesis of chiral azaarenes is great importance for pharmaceutical development. A direct and versatile approach to obtaining such compounds the functionalization imine-containing 2-vinylazaarenes. We have developed a N,N'-dioxide/Mg(II) Lewis acid catalytic system control nucleophilic β-cyclic or acyclic ketone amides/esters overcome strong background reaction, enabling highly efficient enantioselective hydroalkylation 2-vinylazaarenes via conjugate addition. As result, library bearing an all-carbon quaternary stereocenter can be obtained in high yields with good excellent ee values. DFT calculations indicate assistances hydrogen transfer, CH-π interaction between substrate ligand's amide group differentiation.

Язык: Английский

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Conjugate Addition of Chiral Allenylcopper Species to Vinyl Bis(sulfone) To Access an All-Carbon Quaternary Center

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Апрель 1, 2025

Asymmetric formation of all-carbon quaternary centers has been recognized as a challenging area in organic synthesis. Herein, we report copper-catalyzed approach toward coupling two alkenyl substrates, resulting the chiral center. In reaction, axially tetrasubstituted allenylcopper species were generated catalytically and chemoselectively, situ from substituted enynes, remarkably performed an efficient organometallic nucleophile conjugate addition to unsaturated sulfones.

Язык: Английский

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Recent Advances in the Construction of Quaternary Stereocenters via Palladium-Catalyzed Decarboxylative Asymmetric Allylic Alkylation

Synthesis, Год журнала: 2021, Номер 53(23), С. 4341 - 4352

Опубликована: Июнь 22, 2021

Abstract Palladium-catalyzed decarboxylative asymmetric allylic alkylation (DAAA) provides an efficient and powerful strategy to construct quaternary stereocenters, which are widely present in biologically active natural products approved drugs. In this short review, we summarize recent developments (since 2018) the facile synthesis of stereocenters via DAAA methods. Several representative examples use strategies for total complex further demonstrate its synthetic potential realm organic medicinal chemistry. 1 Introduction 2 Construction Quaternary Stereocenters Palladium Catalyzed 3 Pd-Catalyzed Interceptive 4 Application Natural Product Synthesis 5 Conclusion

Язык: Английский

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Metal/Metal Dual Catalysis in C−H Activation

European Journal of Organic Chemistry, Год журнала: 2022, Номер 2022(22)

Опубликована: Май 11, 2022

Abstract Metal/metal dual catalysis provides new viewpoints and opportunities for C−H functionalization, especially in reactivity selectivity control aspects. It helps to realize sequential or cooperative catalytic transformations one‐pot, shortening the synthetic steps target molecules construction. This micro‐review summarizes most recent advances this research field, discusses related mechanism, collecting examples according role of metal species.

Язык: Английский

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Advances in Catalytic Asymmetric Construction of Quaternary Stereogenic Centers by Conjugate Addition to β,β‐Disubstituted Nitroalkenes

Advanced Synthesis & Catalysis, Год журнала: 2023, Номер 365(17), С. 2789 - 2817

Опубликована: Июль 6, 2023

Abstract Quaternary stereogenic centers are of great importance because their prevalence in a series bioactive natural products and pharmaceuticals. Although the catalytic asymmetric construction these highly congested poses formidable challenge, this field has been extensively explored past few decades, several elegant strategies, such as conjugate addition to β,β‐disubstituted nitroalkenes, have developed. The resultant β‐nitro quaternary stereocenters can be conveniently transformed into corresponding β‐amino commonly found compounds. This review summarizes recent advances all‐carbon or hetero‐carbon via metal‐catalyzed organocatalyzed focusing on scope, applications, mechanisms reactions.

Язык: Английский

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Phosphine‐Catalyzed Synthesis and Cytotoxic Evaluation of Michael Adducts of the Sesquiterpene Lactone Arglabin

ChemMedChem, Год журнала: 2024, Номер 19(12)

Опубликована: Март 22, 2024

A general method for chemo- and diastereoselective modification of anticancer natural product arglabin with nitrogen- carbon-centered pronucleophiles under the influence nucleophilic phosphine catalysts was developed. The locked s-cis-geometry α-methylene-γ-butyrolactone moiety favors additional stabilization zwitterionic intermediate by electrostatic interaction between phosphonium enolate oxygen centers, leading to unprecedentedly high efficiency phosphine-catalyzed Michael additions this sesquiterpene lactone. Using n-Bu

Язык: Английский

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Pd(II)/N,N′-Disulfonyl Bisimidazoline-Catalyzed Enantioselective Synthesis of Cyclic Quaternary Centers and Mechanistic Investigations

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(13), С. 9381 - 9388

Опубликована: Июнь 17, 2024

A Pd(II)/N,N′-disulfonyl bisimidazoline-catalyzed asymmetric 1,4-conjugate addition reaction of low-cost arylboronic acids with readily available β-substituted cyclic enones is described, providing a straightforward way constructing all-carbon quaternary stereocenters high enantioselectivity, in which ≥96% ee was obtained most cases. The proceeded without the protection inert gas, making operation process simple. Theoretical calculations have been applied to understand origins enantioselectivity.

Язык: Английский

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A Direct Organocatalytic Enantioselective Route to Functionalizedtrans‐Diels–Alder Products Having the Norcarane Scaffold

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(33), С. 18318 - 18327

Опубликована: Июнь 3, 2021

An enantioselective methodology to construct trans-Diels-Alder scaffolds by organocatalysis with excellent selectivity, high yield and up five contiguous stereocenters is presented. The reaction concept integrates the halogen effect a novel discovered pseudo-halogen direct an endo-selective, secondary-amine catalyzed Diels-Alder allowing for subsequent formation of cycloadducts featuring norcarene scaffold. relies on between in situ generated trienamine α-brominated or α-pseudo-halogenated enone form fleeting cis-Diels-Alder intermediate. endo-transition state-enhanced (pseudo-)halogen effect-sets stereochemistry that allows SN 2-like at tertiary center obtain mechanism was investigated supported experimental results as well computational studies.

Язык: Английский

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