Direct Access to α‐Aminosilanes Enabled by Visible‐Light‐Mediated Multicomponent Radical Cross‐Coupling

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(43), С. 23335 - 23341

Опубликована: Авг. 25, 2021

α-Aminosilanes are an important class of organic compounds that show biological activity. In this communication, a new approach to α-aminosilanes utilizes photoredox catalysis enable three-component coupling organo(tristrimethylsilyl)silanes with feedstock alkylamines and aldehydes is presented. A wide range highly functionalized can be obtained in good yields under mild conditions. Both primary amines secondary compatible transformation. Moreover, optically pure accessible by using chiral amines. Mechanistic studies indicate reactions proceed through radical/radical cross-coupling silyl radicals α-amino alkyl radicals.

Язык: Английский

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Pd/Ming-Phos-Catalyzed Asymmetric Three-Component Arylsilylation of N-Sulfonylhydrazones: Enantioselective Synthesis of gem-Diarylmethine Silanes

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(34), С. 15468 - 15474

Опубликована: Авг. 22, 2022

A Pd-catalyzed enantioselective three-component reaction of N-sulfonylhydrazones, aryl bromides, and silylboronic esters is developed, enabling the synthesis chiral gem-diarylmethine silanes in high enantioselectivity with use a newly identified Ming-Phos. Compared N-tosyl, more easily decomposed N-mesitylsulfonyl suitable as masking group electron-rich hydrazone to improve efficiency. The features broad scope concerning both coupling partners, enantioselectivity, mild conditions. ready access enantiomers utility this catalytic method are also presented.

Язык: Английский

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Electrophilic Activation of S−Si Reagents by Silylium Ions for Their Regio‐ and Diastereoselective Addition Across C−C Multiple Bonds

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(15)

Опубликована: Фев. 7, 2024

Abstract A regioselective silylium‐ion‐promoted thiosilylation of internal C−C triple bonds with control over the double bond geometry is described. Both a C(sp 2 )−S and )−Si are formed trans relationship in this two‐component reaction an alkyne thiosilane. The resulting orthogonally functionalized can be chemoselectively defunctionalized or further processed by cross‐coupling reactions alkene configuration retained. procedure also applicable to regio‐ diastereoselective terminal allenes arrive at allylic thioethers containing vinylsilane unit. These involve electrophilic activation S−Si reagent, both silylated thiophenol even alkylthiol derivative, situ‐generated carbocation intermediate. catalytic cycle maintained bissilylated aryl‐ alkylsulfonium ion as shuttle for cationic silicon electrophile. Its independent preparation structural characterization X‐ray diffraction reported.

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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Nucleophilic Substitution at Unactivated Arene C–H: Copper-Catalyzed anti-Selective Silylative Cyclization of Substituted Benzylacetylenes

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Фев. 13, 2025

A new mode of carbon-carbon bond formation via electrophilic activation a C-H has been developed in the context copper-catalyzed anti-selective silylative cyclization benzylacetylenes with silylboronates for synthesis 2-silyl-1H-indenes. The reaction proceeds high regioselectivity various substituted benzylacetylenes, and resulting products could be further functionalized. arene that undergoes acts as an electrophile release hydride under redox neutral conditions, mechanism was probed by deuterium-labeling experiments density functional theory calculations.

Язык: Английский

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Palladium-Catalyzed Remote Diborylative Cyclization of Dienes with Diborons via Chain Walking

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(46), С. 19275 - 19281

Опубликована: Окт. 25, 2021

A novel method for catalytic remote bismetalation of alkene substrates by the addition dimetal reagents is accomplished using chain walking. In presence a palladium catalyst, reaction various 1,n-dienes and diborons were converted into cyclopentane derivatives with two boryl groups at positions via facile regioselective transformation an unactivated sp3 C-H bond to C-B bond. Sequential construction three distant bonds, which difficult achieve any method, was reactions (n ≥ 7).

Язык: Английский

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Synthesis of Structurally Diverse Allylsilanes via Copper-Catalyzed Regiodivergent Hydrosilylation of 1,3-Dienes

Organic Letters, Год журнала: 2021, Номер 23(12), С. 4736 - 4742

Опубликована: Июнь 7, 2021

Unprecedented copper-catalyzed regiodivergent hydrosilylation reactions of substituted 1,3-dienes with hydrosilanes have been developed. The 1,2- and 1,4-hydrosilylations 1-(hetero)aryl-substituted were highly selectively controlled via variation the catalytic systems. Meanwhile, 1,4-hydrosilylation reaction 2-aryl-substituted diphenylsilane was also successfully realized for first time. These methods provide convenient efficient approaches synthesis structurally diverse allylsilanes.

Язык: Английский

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Enantioselective Nickel-Catalyzed Si–C(sp²) Bond Activation and Migratory Insertion to Aldehydes: Reaction Scope and Mechanism

ACS Catalysis, Год журнала: 2022, Номер 12(8), С. 4571 - 4580

Опубликована: Апрель 4, 2022

Transition-metal-catalyzed silicon–carbon bond activation is one of the most important processes in both organosilicon chemistry and homogeneous catalysis that still rarely reported past decades, enantioselective versions based on transition-metal-catalyzed Si–C remain an ongoing challenge asymmetric catalysis. Herein, we report a convenient cleavage-initiated [4 + 2] annulation benzosilacyclobutenes with aldehydes, which provides access to direct synthesis chiral six-membered oxasilacycles their derivatives high yields enantioselectivities (up 97% ee). The catalytic reaction proceeds smoothly aid TADDOL-derived phosphoramidite ligand its Ni complex suitable cavity. By switching work-up involved, present strategy may be extended subsequent downstream transformations silyl ether-containing give o-tolyl arylmethanols ees quantitative conversions. A series experimental results support silicon-mediated organic controlled by nickel demonstrates powerful potential for facile alcohols drug-like derivatives. Finally, mechanistic computational investigations nickel-catalyzed offer insights into origin observed stereoselective outcome, density functional theory calculation shows nickel-controlled Si–C(sp2) enables controllable migratory insertion benzaldehyde Ni–Si bond, recognized as enantioselectivity-determining step.

Язык: Английский

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KOtBu-Catalyzed 1,2-Silaboration of N-Heteroarenes to Access 2-Silylheterocycles: A Cooperative Model for the Regioselectivity

ACS Catalysis, Год журнала: 2022, Номер 12(9), С. 4898 - 4905

Опубликована: Апрель 11, 2022

Reductive functionalization of N-heteroarenes offers a route to highly versatile heterocyclic synthons bearing multiple transformable groups. We present herein the development KOtBu-catalyzed 1,2-silaboration broad range N-heteroarenes, affording allylamines or enamines with formation sp3 C2–Si bond. These labile compounds were isolated either as their N-acyl derivatives rearomatized 2-silyl-N-heteroarenes by one-pot procedures. A model six-membered ion-pair complex was proposed rationalize observed 1,2-regioselectivity, wherein KOtBu catalyst plays an associative role in activating substrate and silylborane reagent.

Язык: Английский

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Catalytic regio- and stereoselective silicon–carbon bond formations on unsymmetric gem-difluorocyclopropenes by capture of silyl metal species

Organic Chemistry Frontiers, Год журнала: 2022, Номер 9(19), С. 5272 - 5280

Опубликована: Янв. 1, 2022

A highly regioselective silylation of unsymmetric gem -difluorocyclopropenes was achieved by the capture in-situ formed silyl metal intermediates, which gave structurally diverse silyldifluorocyclopropanes with good yields and stereoselectivity.

Язык: Английский

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