Photoinduced Borylation for the Synthesis of Organoboron Compounds

Chemical Reviews, Journal Year: 2021, Volume and Issue: 121(7), P. 3561 - 3597

Published: Feb. 17, 2021

Organoboron compounds have important synthetic value and can be applied in numerous transformations. The development of practical convenient ways to synthesize boronate esters has thus attracted significant interest. Photoinduced borylations originated from stoichiometric reactions alkanes arenes with well-defined metal–boryl complexes. Now, photoredox-initiated borylations, catalyzed by either transition metal or organic photocatalysts, photochemical high efficiency become a burgeoning area research. In this Focus Review, we summarize research on photoinduced especially emphasizing recent developments trends. This includes the borylation arenes, alkanes, aryl/alkyl halides, activated carboxylic acids, amines, alcohols, so based catalysis, metal-free organocatalysis, direct activation. We focus reaction mechanisms involving single-electron transfer, triplet-energy other radical processes.

Language: Английский

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First-Row d-Block Element-Catalyzed Carbon–Boron Bond Formation and Related Processes

Chemical Reviews, Journal Year: 2021, Volume and Issue: 121(21), P. 13238 - 13341

Published: Oct. 7, 2021

Organoboron reagents represent a unique class of compounds because their utility in modern synthetic organic chemistry, often affording unprecedented reactivity. The transformation the carbon–boron bond into carbon–X (X = C, N, and O) stereocontrolled fashion has become invaluable medicinal agrochemistry, natural products chemistry as well materials science. Over past decade, first-row d-block transition metals have increasingly widely used catalysts for formation bond, traditionally catalyzed by expensive precious metals. This recent focus on alternative enabled growth fundamental methods organoboron chemistry. review surveys current state-of-the-art use element-based bonds.

Language: Английский

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Carbazole‐Based DABNA Analogues as Highly Efficient Thermally Activated Delayed Fluorescence Materials for Narrowband Organic Light‐Emitting Diodes

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 60(6), P. 2882 - 2886

Published: Nov. 12, 2020

Abstract Carbazole‐based DABNA analogues ( CzDABNA s) were synthesized from triarylamine by regioselective one‐shot single and double borylation. The reaction proceeded selectively at the ortho position of carbazolyl group, where highest occupied molecular orbital is mainly localized owing to difference in electron‐donating abilities diarylamino groups. facile scalable method enabled synthesis s, exhibiting narrowband thermally activated delayed fluorescence with emission spectra ranging deep blue green. organic light‐emitting diode devices employing these products as emitters exhibited deep‐blue, sky‐blue, green high external quantum efficiencies 19.5, 21.8, 26.7 %, respectively.

Language: Английский

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Near-Infrared-Absorbing B–N Lewis Pair-Functionalized Anthracenes: Electronic Structure Tuning, Conformational Isomerism, and Applications in Photothermal Cancer Therapy

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(41), P. 18908 - 18917

Published: Oct. 4, 2022

B–N-fused dianthracenylpyrazine derivatives are synthesized to generate new low gap chromophores. Photophysical and electrochemical, crystal packing, theoretical studies have been performed. Two energetically similar conformers identified by density functional theory calculations, showing that the core unit adopts a curved saddle-like shape (x-isomer) or zig-zag conformation (z-isomer). In solid state, z-isomer is prevalent according an X-ray structure of C6F5-substituted derivative (4-Pf), but variable-temperature nuclear magnetic resonance suggest dynamic behavior in solution. B–N fusion results large decrease HOMO–LUMO dramatically lowers LUMO energy compared all-carbon analogues. 4-Pf particular shows significant absorbance at greater than 700 nm while being almost transparent throughout visible region. After encapsulation biodegradable polymer DSPE-mPEG2000, nanoparticles (4-Pf-NPs) exhibit good water solubility, high photostability, excellent photothermal conversion efficiency ∼41.8%. 4-Pf-NPs evaluated both vitro vivo as therapeutic agents. These uncover Lewis pair functionalization PAHs promising strategy toward NIR-absorbing materials for applications.

Language: Английский

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Metal-catalysed C–H bond activation and borylation

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(12), P. 5042 - 5100

Published: Jan. 1, 2022

Transition metal-catalysed direct borylation of hydrocarbons via C–H bond activation has received a remarkable level attention as popular reaction in the synthesis organoboron compounds owing to their synthetic versatility.

Language: Английский

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From C4 to C7: Innovative Strategies for Site-Selective Functionalization of Indole C–H Bonds

Accounts of Chemical Research, Journal Year: 2021, Volume and Issue: 54(7), P. 1723 - 1736

Published: March 12, 2021

The widespread presence of hydrocarbons makes C-H functionalization an attractive alternative to traditional cross-coupling methods. As indole is important heteroarene in a plethora natural products and pharmaceuticals, moieties has emerged as one the most topics this field. Due multiple bonds indoles, site selectivity long-standing challenge. Much effort been devoted indoles at C3 or C2 position, while accessing benzene core (from C4 C7) considerably more challenging.This Account summarizes our recent efforts toward site-selective based on innovative strategies. A common method solve issue involves development directing groups (DGs). Our early studies establish that installation N-P(O)tBu2 group N position can produce C7 C6 arylation using palladium copper catalysts, respectively. developed system also be extended direct C5 positions by installing pivaloyl position. Further investigation bearing N-PtBu2 shows diverse reactivity for functionalizations including arylation, olefination, acylation, alkylation, silylation, carbonylation with different coupling partners. Compared P(V) DG, P(III) easily attached substrates detached from products. However, these reactions rely mostly precious metal catalysts ligands; requirement significant limitation, particularly large-scale syntheses necessity removal toxic trace metals pharmaceutical We have uncovered general strategy chelation-assisted aromatic borylation just simple BBr3 under mild conditions, which N1 selectively deliver boron species unfavorable allow subsequent without any metal. This transition-metal-free synthesize hydroxylated boron-mediated directed hydroxylation reaction conditions broad functional compatibility.In Account, we describe contributions topic since 2015. These provide efficient methods divergent synthesis valuable substituted insights into exploration new strategies directives other heteroarenes.

Language: Английский

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Recent advances in asymmetric borylation by transition metal catalysis

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(23), P. 13129 - 13188

Published: Jan. 1, 2021

We provide a comprehensive overview of transition metal-catalysed asymmetric borylation processes to construct C–B, C–C, and other C–heteroatom bonds with considerable attention devoted the reaction modes mechanisms involved.

Language: Английский

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Fusion of Multi‐Resonance Fragment with Conventional Polycyclic Aromatic Hydrocarbon for Nearly BT.2020 Green Emission

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(24)

Published: April 1, 2022

Herein, we report a general strategy for achieving ultra-pure green emissions by suppressing the shoulder peaks in emission spectra of conventional polycyclic aromatic hydrocarbons (PAHs). Through precise synthetic fusion multi-resonance (MR) fragments with PAH, extended π-conjugation lengths, increased molecular rigidity, and reduced vibrational frequency could be simultaneously realized. The proof-of-concept emitters exhibited dominant at ca. 521 nm, photoluminescence quantum yields that are greater than 99 %, small full-width-at-half-maximum 23 CIE coordinates (0.16, 0.77). bottom-emitting organic light-emitting diode (OLED) record-high CIEy value 0.74 high maximum external efficiency 30.5 %. top-emitting OLED not only achieved BT.2020 color (CIE: 0.17, 0.78) first time but also showed superior performance among all devices, current 220 cd A- .

Language: Английский

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Recent Advances in Metal‐Catalyzed Functionalization of Indoles

Advanced Synthesis & Catalysis, Journal Year: 2021, Volume and Issue: 363(11), P. 2723 - 2739

Published: April 7, 2021

Abstract Indole is one of the most important heterocycles in organic synthesis, natural products, and drug discovery. Recently, tremendous advances selective functionalization indoles have been reported. Although powered by transition metal catalysis, exceedingly useful methods absence metals also In this review, we provide an overview reactions that published last years with a focus on recent advances, aims, future trends. The review organized positional selectivity type used for functionalization. particular, discuss major transition‐metal‐catalyzed C−H at classical C2/C3 positions, remote C4/C7 cross‐coupling, transition‐metal‐free magnified image

Language: Английский

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Organoboron-based multiple-resonance emitters: synthesis, structure–property correlations, and prospects

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(3), P. 1624 - 1692

Published: Jan. 1, 2024

This review highlights organoboron-based multiple-resonance compounds’ synthetic strategies classified as one-pot borylation, one-shot and late-stage functionalisation, explores material structure–photophysical property correlations.

Language: Английский

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