Nickel‐Catalyzed Switchable Site‐Selective Alkene Hydroalkylation by Temperature Regulation**

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(31)

Опубликована: Май 25, 2022

Regiodivergent alkene functionalization that produces either regioisomer starting from the same raw materials is desirable. Herein, we report a nickel-catalyzed switchable site-selective hydroalkylation. The selection of reaction temperatures leads to protocols provide regiodivergent hydroalkylated products single substrate. This protocol allows convenient synthesis α- and β-branched protected amines, both which are important fields pharmaceutical chemistry biochemistry. In addition, enantioenriched alkylamines can be accessed in catalytic asymmetric variant. Preliminary mechanistic studies indicate formation more stable nickelacycle provides driving force migration. thermodynamic kinetic properties different reduction elimination intermediates responsible for site-selectivity.

Язык: Английский

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Visible light catalyzed arylsilylation of alkenes to construct silicon-containing 1,1-diaryl moieties

Green Chemistry, Год журнала: 2024, Номер 26(8), С. 4785 - 4791

Опубликована: Янв. 1, 2024

We have developed an efficient photocatalyzed arylsilylation of alkenes, utilizing silylboranes and (hetero)aryl nitriles in the presence base photocatalyst.

Язык: Английский

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Bifunctional Copper Metal–Organic Framework Catalyst for Late-Stage Functionalization of Alkenes

ACS Catalysis, Год журнала: 2025, Номер unknown, С. 4198 - 4207

Опубликована: Фев. 24, 2025

Язык: Английский

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Nickel‐Catalyzed Enantioconvergent Carboxylation Enabled by a Chiral 2,2′‐Bipyridine Ligand

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(51)

Опубликована: Окт. 27, 2022

In contrast to previous approaches chiral α-aryl carboxylic acids that based on reactions using hazardous gases, pressurized setup and mostly noble metal catalysts, in this work, a nickel-catalyzed general, efficient highly enantioselective carboxylation reaction of racemic benzylic (pseudo)halides under mild conditions atmospheric CO2 has been developed. A unique 2,2'-bipyridine ligand named Me-SBpy featuring compact polycyclic skeleton enabled both high reactivity stereoselectivity. The utility method demonstrated by synthesis various (30 examples, up 95 % yield 99 : 1 er), including profen family anti-inflammatory drugs transformations the as key intermediates. Based mechanistic experimental results, plausible catalytic cycle involving Ni-complex/radical equilibrium Lewis acid-assisted activation proposed.

Язык: Английский

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Ligand-enabled Ni-catalyzed hydroarylation and hydroalkenylation of internal alkenes with organoborons

Nature Communications, Год журнала: 2022, Номер 13(1)

Опубликована: Ноя. 12, 2022

The transition metal-catalyzed hydrofunctionalization of alkenes offers an efficient solution for the rapid construction complex functional molecules, and significant progress has been made during last decades. However, internal remains a challenge due to low reactivity difficulties controlling regioselectivity. Here, we report hydroarylation hydroalkenylation lacking directing group with aryl alkenyl boronic acids in presence nickel catalyst, featuring broad substrate scope wide tolerance under redox-neutral conditions. key achieving this reaction is identification bulky 1-adamantyl β-diketone ligand, which capable overcoming 1,2-disubstituted alkenes. Preliminary mechanistic studies unveiled that undergoes Ar-Ni(II)-H initiated process, generated by oxidative addition alcoholic solvent Ni(0) species sequential transmetalation. In addition, proves be turnover-limiting step.

Язык: Английский

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Switchable Direct Oxygenative Arylation of C(sp³)–H Bonds via Electrophotocatalysis

Organic Letters, Год журнала: 2023, Номер 25(27), С. 5067 - 5072

Опубликована: Июнь 30, 2023

A metal-free electrophotochemical C(sp3)-H arylation was developed under mild conditions. This method enables a switchable synthesis of diaryl alcohols and alkanes from inactive benzylic carbons. More importantly, cheap safe mediator N-chlorosuccinimide (NCS) developed, which employed for the hydrogen atom transfer (HAT) process C–H bond. In addition, this active radical captured identified by electron paramagnetic resonance (EPR).

Язык: Английский

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Lewis Basic Salt-Promoted Organosilane Coupling Reactions with Aromatic Electrophiles

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(31), С. 11939 - 11945

Опубликована: Июль 27, 2021

Lewis basic salts promote benzyltrimethylsilane coupling with (hetero)aryl nitriles, sulfones, and chlorides as a new route to 1,1-diarylalkanes. This method combines the substrate modularity selectivity characteristic of cross-coupling practicality base-promoted protocol. In addition, base strategy enables complementary scope existing methods, employs stable easily prepared organosilanes, achieves selective arylation in presence acidic functional groups. The utility this is demonstrated by synthesis pharmaceutical analogues its use multicomponent reactions.

Язык: Английский

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Rhodium(I) Carbene‐Promoted Enantioselective C−H Functionalization of Simple Unprotected Indoles, Pyrroles and Heteroanalogues: New Mechanistic Insights

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(34)

Опубликована: Июнь 17, 2022

A rhodium(I)-diene catalyzed highly enantioselective C(sp2 )-H functionalization of simple unprotected indoles, pyrroles, and their common analogues such as furans, thiophenes, benzofurans with arylvinyldiazoesters has been developed for the first time. This transformation features unusual site-selectivity exclusively at vinyl terminus arylvinylcarbene enables a reliable rapid synthetic protocol to access distinctive class diarylmethine-bearing α,β-unsaturated esters containing one or two heteroarene-attached tertiary carbon stereocenter in high yields excellent enantioselectivities under mild reaction conditions. Mechanistic studies DFT calculations suggest that, compared aniline substrate, more electron-rich indole substrate lowers C-C addition barrier alters rate-determining step reductive elimination, leading different isotope effect.

Язык: Английский

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Efficient Synthesis of Diaryl Quaternary Centers by Rh(II)/Xantphos Catalyzed Relay C−H Functionalization and Allylic Alkylation

Chemistry - A European Journal, Год журнала: 2022, Номер 29(3)

Опубликована: Окт. 14, 2022

A three-component reaction of N, N-disubstituted aniline, α-diazo ester, and an allylic electrophile has been realized by [Rh(II)]2 /Xantphos catalysis, providing a direct access to various aniline derivatives bearing diaryl quaternary centers in good yields. The synthetic utility this protocol was demonstrated facile derivatization the products for preparation biologically relevant molecules structural scaffolds, which offers high potential increasing molecular diversity. Mechanistic studies identified α, α-diarylacetate species as active intermediate, thereby revealing presence C(sp2 )-H functionalization derivatives/allylic alkylation cascade attractive catalytic transformation.

Язык: Английский

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Conformational Locking Induced Enantioselective Diarylcarbene Insertion into B−H and O−H Bonds Using a Cationic Rh(I)/Diene Catalyst

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(45)

Опубликована: Июль 18, 2024

Abstract Transition‐metal‐catalyzed enantioselective transformations of aryl/aryl carbene are inherently challenging due to the difficulty in distinguishing between two arene rings reaction process thus remain largely less explored. The few successful examples reported so far, without exception, have all been catalyzed by Rh(II)‐complexes. Herein, we describe our development a novel cationic Rh(I)/chiral diene catalytic system capable efficient B−H and O−H insertions with diaryl diazomethanes, allowing access broad range gem ‐diarylmethine boranes ethers good yields high enantioselectivities. Notably, previously unattainable asymmetric diarylcarbene insertion into bond was achieved for first time. A remarkable feature this newly designed Rh(I)/diene catalyst bearing ortho ‐amidophenyl substitutents is that it can distinguish through stereochemically selective control π–π stacking interactions. DFT calculations indicate rotation‐restricted conformation complex played an important role highly transformations. This work provides interesting unprecedented stereocontrol mode metal

Язык: Английский

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