Triarylborane Catalyzed Carbene Transfer Reactions Using Diazo Precursors

ACS Catalysis, Год журнала: 2021, Номер 12(1), С. 442 - 452

Опубликована: Дек. 17, 2021

Reactive carbenes generated from diazo compounds are key intermediates for a range of organic reactions to afford synthetically useful compounds. The majority these have been carried out using transition metal catalysts. However, the formation carbene main group elements has not widely investigated synthetic purposes. Recent studies demonstrated that triarylboranes can be used in situ generation reactive both stoichiometric and catalytic reactions. These new reactivities gained significant attention chemistry particularly studies. synthesized through important as pharmaceuticals or agrochemicals. In this perspective, we highlight recent progress ongoing challenges transfer their corresponding precursors We also use which boranes only activate functionality intermediate but actively participate reagent. different mechanisms activation described along with mechanistic computational aided elucidation reaction pathways. Potential opportunities catalyst toward future prospects discussed.

Язык: Английский

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B(C6F5)3-catalyzed selective C–H chalcogenation of arenes and heteroarenes

Chem, Год журнала: 2024, Номер 10(9), С. 2901 - 2915

Опубликована: Июнь 27, 2024

The synthesis of organochalcogenides remains a valuable area research due to their widespread biological applications, particularly in pharmaceuticals. Herein, our study details the B(C6F5)3-catalyzed Csp2–H functionalization diverse arenes, heteroarenes, and pharmacophores with thiosuccinimides or selenosuccinimides, providing selective access chalcogenated products. This protocol enables late-stage chalcogenation drug molecules such as anti-inflammatory naproxen, estrogen steroid hormone estradiol derivatives, industrially relevant trifluoromethylthiolation reaction. Furthermore, this C–S coupling methodology provides facile metal-free route synthesize vortioxetine, an antidepressant drug, plethora significant organic motifs. Detailed NMR, EPR analyses, density functional theory (DFT) computational studies indicate that elongation thiosuccinimide N–S bond is assisted by boron-centered adduct, which then leads stable ion pair arene. analysis shows transient radical pair, potentially off-cycle species, not directly involved catalytic process.

Язык: Английский

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Visible Light-Promoted Diazoacetates and Nitriles Generating Nitrilium Ions Trapped by Benzotriazoles and Carboxylic Acids

Organic Letters, Год журнала: 2022, Номер 24(31), С. 5855 - 5859

Опубликована: Авг. 2, 2022

A visible light-promoted generation of nitrilium ions from diazoacetates and nitriles has been developed. The reaction utilized light transformation to the free carbene that could be trapped by generate ions, followed nucleophilic attack on benzotriazoles carboxylic acids. This protocol provides an efficient practical approach N-imidoylbenzotriazoles diacylglycine esters in good excellent yields.

Язык: Английский

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B(C₆F₅)₃-catalyzed cyclopropanation of 3-alkenyl-oxindoles with diazomethanes

Chemical Communications, Год журнала: 2023, Номер 59(13), С. 1833 - 1836

Опубликована: Янв. 1, 2023

Spirocyclopropane-oxindoles are key motifs in biologically active compounds and versatile synthetic intermediates. Herein, we report a metal-free, B(C6F5)3 catalyzed cyclopropanation of 3-alkenyl-oxindoles with diazomethanes. This provides 25 variants spirocyclopropane-oxindole derivatives. These products were obtained good to excellent yields (up 99%) high diastereoselectivities 20 : 1 d.r.) under mild reaction conditions could be performed on gram scale.

Язык: Английский

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B(C₆F₅)₃-catalyzed Wolff rearrangement/[2 + 2] and [4 + 2] cascade cyclization of α-diazoketones with imines

Organic Chemistry Frontiers, Год журнала: 2023, Номер 10(7), С. 1754 - 1758

Опубликована: Янв. 1, 2023

B(C 6 F 5 ) 3 -catalyzed [2 + 2] cyclizations of α-diazoketones with N-tert -butoxycarbonyl imines affords 20 β-lactams in up to 94% yield, while reactions N -benzoyl gave 14 oxazinone derivatives 95% yield.

Язык: Английский

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Tris(pentafluorophenyl)borane‐Catalyzed Carbenium Ion Generation and Autocatalytic Pyrazole Synthesis—A Computational and Experimental Study

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(46), С. 24395 - 24399

Опубликована: Сен. 30, 2021

In recent years, metal-free organic synthesis using triarylboranes as catalysts has become a prevalent research area. Herein we report comprehensive computational and experimental study for the highly selective of N-substituted pyrazoles through generation carbenium species from reaction between aryl esters vinyl diazoacetates in presence catalytic tris(pentafluorophenyl)borane [B(C6 F5 )3 ]. DFT studies were undertaken to illuminate mechanism revealing that situ acts an autocatalyst prompt regiospecific formation good excellent yields (up 81 %).

Язык: Английский

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Understanding the Influence of Donor‐Acceptor Diazo Compounds on the Catalyst Efficiency of B(C₆F₅)₃ Towards Carbene Formation

Chemistry - A European Journal, Год журнала: 2021, Номер 28(11)

Опубликована: Дек. 27, 2021

Diazo compounds have been largely used as carbene precursors for transfer reactions in a variety of functionalization reactions. However, the ease generation from corresponding diazo depends upon electron donating/withdrawing substituents either side functionality. These groups strongly impact N

Язык: Английский

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Activation of Diazo Compounds by Fluorinated Triarylborane Catalysts

Synthesis, Год журнала: 2023, Номер 55(23), С. 3906 - 3918

Опубликована: Июнь 27, 2023

Abstract The diverse applicability of diazo compounds as versatile reagents has enlarged the chemical toolbox in organic synthesis. Over past few decades, transition-metal-catalyzed compound activation ignited classical synthetic methodology via utilizing highly reactive metal carbenoid species. Many reviews have also appeared literature that show advantages and disadvantages metal-catalyzed compounds. Recently, tris(pentafluorophenyl)borane-mediated reactions remodeled this research area due to potential for mild, environmentally friendly, metal-free, nontoxic reaction conditions, reactivity patterns boranes towards In review, we discuss boron–diazo precursor adducts with using catalytic stoichiometric halogenated triarylboranes and, mechanism N2 release from reagent. This generates carbene species a key intermediate which can further be exploited O–H, N–H, S–H, C–H insertions, azide insertion, carbonate transfer, C–C C=C bond forming reactions, [2+2] or [2+4] cascade cyclization annulation etc. 1 Introduction 2 Diazo Activation Using Stoichiometric Boranes 3 Catalytic B(C6F5)3 4 B(C6F5)3-Catalyzed Reactions 5 Conclusions

Язык: Английский

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Borane-Catalyzed Coupling of Diazooxindoles and Difluoroenoxysilanes to Tetrasubstituted Monofluoroalkenes

Organic Letters, Год журнала: 2024, Номер 26(26), С. 5539 - 5543

Опубликована: Июнь 24, 2024

A highly stereoselective coupling reaction of diazooxindoles with difluoroenoxysilanes catalyzed by Lewis acidic boranes has been developed. The proceeded at ambient temperature under transition metal-free conditions wide functional group tolerance. By using this simple procedure, a series tetrasubstituted monofluoroalkenes can be accessed in good yield high selectivity.

Язык: Английский

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Comparison of the Efficiency of B–O and B–C Bond Formation Pathways in Borane-Catalyzed Carbene Transfer Reactions Using α-Diazocarbonyl Precursors: A Combined Density Functional Theory and Machine Learning Study

ACS Catalysis, Год журнала: 2024, Номер 14(19), С. 14486 - 14496

Опубликована: Сен. 16, 2024

Lewis acidic boranes, especially tris(pentafluorophenyl)borane [B(C

Язык: Английский

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