Electroreduction of unactivated alkenes using water as hydrogen source

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Март 30, 2024

Abstract Herein, we report an electroreduction of unactivated alkyl alkenes enabled by [Fe]-H, which is provided through the combination anodic iron salts and silane generated in situ via cathodic reduction, using H 2 O as H-source. The catalytic amounts Si-additive work H-carrier from to generate a highly active species under continuous electrochemical conditions. This approach shows broad substrate scope good functional group compatibility. In addition hydrogenation, use D instead provides desired deuterated products yields with excellent D-incorporation (up >99%). Further late-stage hydrogenation complex molecules drug derivatives demonstrate potential application pharmaceutical industry. Mechanistic studies are performed provide support for proposed mechanistic pathway.

Язык: Английский

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Phenanthroline-imine ligands for iron-catalyzed alkene hydrosilylation

Chemical Science, Год журнала: 2022, Номер 13(9), С. 2721 - 2728

Опубликована: Янв. 1, 2022

Iron-catalyzed organic reactions have been attracting increasing research interest but still serious limitations on activity, selectivity, functional group tolerance, and stability relative to those of precious metal catalysts. Progress in this area will require two key developments: new ligands that can impart reactivity iron catalysts elucidation the mechanisms catalysis. Herein, we report development novel 2-imino-9-aryl-1,10-phenanthrolinyl complexes catalyze both

Язык: Английский

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Highly Regio‐, Stereo‐, and Enantioselective Copper‐Catalyzed B−H Bond Insertion of α‐Silylcarbenes: Efficient Access to Chiral Allylic gem‐Silylboranes

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(26)

Опубликована: Апрель 19, 2022

Herein, we report the development of a method for highly regio-, stereo-, and enantioselective B-H bond insertion reactions α-silylcarbenes generated from 1-silylcyclopropenes in presence chiral copper(I)/bisoxazoline catalyst construction γ,γ-disubstituted allylic gem-silylboranes, which cannot be prepared by any other known methods. This reaction is first carbene ever to reported. The shows general applicability various 3,3-disubstituted silylcyclopropenes exclusively affords E-products. novel gem-silylborane products are versatile bimetallic reagents with high stability have great synthetic potential, especially complex molecules continuous centers.

Язык: Английский

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Highly Regioselective Cobalt‐Catalyzed Hydroboration of Internal Alkynes

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(36)

Опубликована: Июль 13, 2022

Herein, we report the development of new Co complexes that have cyclopropane-based diphosphine ligands and can catalyze highly chemo-, regio-, stereoselective hydroboration reactions unsymmetrical internal alkynes. These exhibited unusual regioselectivity: specifically, aryl alkyl alkynes showed excellent cis-β-addition selectivity, dialkyl gave cis-α-addition selectivity. Highly regioselective cannot be achieved by other known methods. The described herein are synthetically useful, particularly for synthesis trisubstituted alkenylborates alkenes. Mechanistic studies indicate a CoI -H species is plausible active catalyst rigid structure cyclopropane skeleton crowded reaction pocket were responsible unprecedented regioselectivity.

Язык: Английский

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Iron-Catalyzed C(sp³)–C(sp³) Coupling to Construct Quaternary Carbon Centers

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(8), С. 5051 - 5055

Опубликована: Фев. 19, 2024

The construction of quaternary carbon centers via C–C coupling protocols remains challenging. tertiary C(sp3) with secondary or counterparts has been hindered by pronounced steric clashes and many side reactions. Herein, we have successfully developed a type bisphosphine ligand iron complex-catalyzed reactions alkyl halides zinc reagents efficiently realized the reaction between high selectivity for initial instance, which provided an efficient method hindrance. combination catalyst directing group substrate makes great challenging transformation possible.

Язык: Английский

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Iron-Catalyzed Alkylzincation of Terminal Alkynes

ACS Catalysis, Год журнала: 2022, Номер 12(4), С. 2581 - 2588

Опубликована: Фев. 7, 2022

Although carbozincation of terminal alkynes is a promising method for the synthesis alkenylzinc reagents, many challenges, especially chemo-, regio-, and stereoselectivity, remain to be addressed. Herein we report an operationally simple, mild iron-catalyzed alkylzincation produce diverse array compounds in high yields with anti-Markovnikov selectivity cis stereoselectivity. Using this method, realized alkynes, demonstrated that has wide substrate scope (being suitable aryl-, alkenyl-, alkyl-, heteroatom-substituted acetylenes) good functional group tolerance. Because C(sp2)─Zn bonds products can readily transformed, provides competitive alternative traditional methods selective trisubstituted olefins. The iron catalyst developed study exhibited irreplaceable reactivity alkyne

Язык: Английский

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Catalytic Asymmetric Synthesis of Chiral Propargylic Boron Compounds through B–H Bond Insertion Reactions

ACS Catalysis, Год журнала: 2022, Номер 12(17), С. 10654 - 10660

Опубликована: Авг. 16, 2022

Chiral propargylic boron compounds have a diverse array of potential applications. Although numbers highly enantioselective methodologies for the synthesis other organoboron are well established, chiral remains unknown. Herein, we report catalytic method construction by means dirhodium-catalyzed B–H bond insertion reactions using aryl sulfonylhydrazones as carbene precursors. This enables straightforward wide range stable in yields up to 99% with enantioselectivities 97% ee. The operationally simple features broad substrate scope, good functional group tolerance, and mild reaction conditions. prepared this study inaccessible known methods exhibit high utility because they could be efficiently transformed into allenyl borates, triazole borane compounds, homopropargylic alcohols enantiomeric fidelity. Our work expands library reactions, increases variety that can synthesized, provides preliminary information about possible transformations thus laying foundation application these compounds.

Язык: Английский

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Iron‐Catalyzed Allylic C(sp³)−H Silylation: Spin‐Crossover‐Efficiency‐Determined Chemoselectivity

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(21)

Опубликована: Март 12, 2024

Abstract The nuanced role of spin effects remains a critical gap in designing proficient open‐shell catalysts. This study elucidates an iron‐catalyzed allylic C( sp 3 )−H silylation/alkyne hydrosilylation reaction, which the state iron catalyst dictates reaction kinetics and pathway. Specifically, crossover led to alkyne hydrosilylation, whereas conservation resulted novel silylation reaction. chemoselectivity, governed by spin‐crossover efficiency, reveals unexpected dimension first realm transition‐metal‐catalyzed situ bonds, had been previously inhibited heightened reactivity alkenes reactions. Furthermore, this can either accelerate or hinder at different stages within single catalytic phenomenon scarcely documented. Moreover, we identify substrate‐assisted C−H activation mechanism, departure from known ligand‐assisted processes, offering fresh perspective on strategies.

Язык: Английский

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Imidodiphosphorimidates (IDPis): Catalyst Motifs with Unprecedented Reactivity and Selectivity

Chinese Journal of Chemistry, Год журнала: 2022, Номер 41(6), С. 685 - 694

Опубликована: Ноя. 12, 2022

Abstract The conceptually designed imidodiphosphorimidates (IDPis) have emerged as one of the most potent classes chiral acid catalysts. They are characterized by enzyme‐like, highly confined active site and high acidity, which underlie their wide‐reaching applications Brønsted catalysts precatalysts for silylium Lewis acids. Many carbon‐carbon carbon‐heteroatom bond formation reactions that were deemed intractable could now be attained with spectacular reactivity selectivity. Substrates small, unbiased and/or possess insufficient such simple alkenes engaged. structural confinement is particularly invaluable to control stereo‐ chemoselectivity. well‐defined steric environment offers unique opportunity high‐energy but structurally cation intermediates norbonyl cations. Beyond practical appeals good scalability well ease modularity preparation, extremely low pre‐catalyst loadings required achieve turnover stereoselectivity also come define a new frontier in organocatalysis.

Язык: Английский

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Catalytic Asymmetric P–H Insertion Reactions

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(36), С. 20031 - 20040

Опубликована: Авг. 29, 2023

Albeit notable endeavors in enantioselective carbene insertion into X–H bonds (X = C, O, N, S, Si, B), the catalytic asymmetric P–H reactions still stand for a long-lasting challenge. By merging transition-metal catalysis with organocatalysis, we achieve scalable transformation between diazo pyrazoleamides and H-phosphine oxides that upon subsequent reduction delivers wide variety of optically active β-hydroxyl phosphine good yields high enantioselectivity. The achiral copper catalyst fosters carbenoid bond, while chiral cinchona alkaloid-derived organocatalyst controls outcome. Density functional theory (DFT) calculations further reveal chelates to organocatalyst, enhances its acidity, accordingly promotes proton transfer. Our work showcases potential combining organocatalysis realize elusive reactions.

Язык: Английский

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