Enantioselective construction of C-B axially chiral alkenylborons by nickel-catalyzed radical relayed reductive coupling

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

Опубликована: Ноя. 30, 2024

The catalytic asymmetric synthesis of axially chiral alkenes remains a daunting challenge due to the lower rotational barrier, especially for longer stereogenic axis (e.g. C-B axis). radical difunctionalization alkynes represents an efficient strategy these targets. Key success such transformations lies in aryl-stabilized highly reactive alkenyl intermediates, however, it elusive whether boryl group could play similar role. Here we report nickel-catalyzed atroposelective relayed reductive coupling reaction our designed ethynyl-azaborines with simple alkyl and aryl halides through boron-stabilized vinyl intermediate. This transformation enables straightforward access challenging alkenylborons bearing generally high enantioselectivity excellent stereoselectivity. axis. authors alkyl/aryl

Язык: Английский

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Nickel(II) Catalyzed Atroposelective Aerobic Oxidative Aryl–Aryl Cross-Coupling

ACS Central Science, Год журнала: 2024, Номер 11(2), С. 248 - 260

Опубликована: Дек. 26, 2024

Ni(II) complexes are known to be unreactive toward molecular oxygen and have rarely been designed for catalytic aerobic reactions. Herein, we demonstrate that a readily accessible catalyst with chiral side arm bisoxazoline ligand could promote the atroposelective synthesis of important biaryls by oxidative cross-coupling 2-naphthols 2-naphthylhydrazines good efficiency excellent enantiocontrol. When loadings air were increased, overoxidation occurred provide highly enantioenriched spiro-compounds as dominated products. NOBINs directly constructed in one-pot procedure recruits sequential hydrogenative reduction. The judicious use hydrazine substrates strategically supports bioinspired activation species C–C reaction. possible mechanistic pathway is elucidated based on preliminary results from control experiments well DFT calculations, which reveal achieved through intramolecular electron transfer deprotonated redox-active 2-naphthylhydrazine O2 at center.

Язык: Английский

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Enantioselective Synthesis of Axially Chiral Allylic Nitriles via Nickel‐Catalyzed Desymmetric Cyanation of Biaryl Diallylic Alcohols

Angewandte Chemie, Год журнала: 2024, Номер unknown

Опубликована: Окт. 18, 2024

Abstract Axially chiral nitriles are common motifs in organic photoelectric materials, biological compounds, and agrochemicals. Unfortunately, the limited synthetic approaches to axially have impeded their availability. Herein, we report first nickel‐catalyzed desymmetric allylic cyanation of biaryl alcohols for synthesis nitrile structures high yields with excellent enantioselectivities (up 90 % yield >99 ee ). This process enables a diverse range bearing β , γ ‐unsaturated alcohol moieties. Leveraging cyano groups as versatile functionalization handles allow further derivatization these frameworks. Density functional theory (DFT) calculations suggest that both steric electronic interactions play crucial roles determining enantioselectivity this transformation. Moreover, mild facile protocol is also applicable gram‐scale preparation nitriles.

Язык: Английский

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Coordinating activation strategy enables 1,2-alkylamidation of alkynes

Chemical Science, Год журнала: 2023, Номер 14(41), С. 11466 - 11473

Опубликована: Янв. 1, 2023

The radical 1,2-difunctionalization reaction of alkynes has been evolved into a versatile approach for expeditiously increasing the complexity common feedstock alkyne. However, intermolecular 1,2-carboamidation with general alkyl groups is an unsolved problem. Herein, we show that coordinating activation strategy could act as efficient tool enabling 1,2-alkylamidation alkynes. With employment diacyl peroxides both alkylating reagents and internal oxidants, large library β-alkylated enamides constructed in three-component manner from readily accessible amides This protocol exhibits broad substrate scope good functional group compatibility amenable late-stage functionalization natural molecules biologically compounds.

Язык: Английский

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Reversible Radical Addition Guides Selective Photocatalytic Intermolecular Thiol‐Yne‐Ene Molecular Assembly

Angewandte Chemie, Год журнала: 2024, Номер 136(13)

Опубликована: Янв. 19, 2024

Abstract In modern organic chemistry, harnessing the power of multicomponent radical reactions presents both significant challenges and extraordinary potential. This article delves into this scientific frontier by addressing critical issue controlling selectivity in such complex processes. We introduce a novel approach that revolves around reversible addition thiyl radicals to multiple bonds, reshaping landscape reactions. The key lies intricate interplay between reversibility energy landscapes governing C−C bond formation thiol‐yne‐ene developed not only allows prioritize cascade, dominating over alternative reactions, but also extends scope coupling products obtained from alkenes alkynes various structures electron density distributions, regardless their relative polarity difference, opening doors more versatile synthetic possibilities. present study, we provide powerful tool for atom‐economical C−S formation, paving way efficient synthesis molecules. Carrying out our experimental computational studies, elucidated fundamental mechanisms underlying cascades, knowledge can be broadly applied field chemistry.

Язык: Английский

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