Light-Enabled Reversible Hydrogen Storage of Borohydrides Activated by Photogenerated Vacancies

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Янв. 10, 2025

Borohydrides, known for ultrahigh hydrogen density, are promising storage materials but typically require high operating temperatures due to their strong thermodynamic stability. Here we introduce a novel light-induced destabilization mechanism reaction of borohydrides under ambient conditions via photogenerated vacancies in LiH. These thermodynamically destabilize B–H bonds through the spontaneous "strong adsorption" BH4 groups, which trigger an asymmetric redistribution electrons, enabling release at near room temperature, approximately 300 °C lower than corresponding thermal process. By utilizing specially designed "nano-photothermal reactors", optimize effect with nanoscale dispersed LiH and create space-confined "hotspots" enhance kinetics, achieve capacity 11.02 wt % H2 LiBH4 using only light irradiation. This can also be extended other alkali metal borohydrides, offering insights developing solid-state mild conditions.

Язык: Английский

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Iron-Catalyzed Hydrobenzylation: Stereoselective Synthesis of (−)-Eugenial C

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(29), С. 15714 - 15720

Опубликована: Июль 12, 2023

Metal-hydride hydrogen atom transfer (MHAT) has emerged as a useful tool to form quaternary carbons from alkenes via hydrofunctionalization. Methods date that cross-couple with sp3 partners rely on heterobimetallic catalysis merge the two cycles. Here, we report an iron-only cross-coupling putative MHAT/SH2 steps solves key stereochemical problem in synthesis of meroterpenoid eugenial C and obviates need for nickel. The concise benefits conformationally locked o,o′-disubstituted benzyl bromide locally sourced chiral pool terpene coupling partner.

Язык: Английский

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A General Light‐Driven Organocatalytic Platform for the Activation of Inert Substrates

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(32)

Опубликована: Июнь 16, 2023

Due to their strong covalent bonds and low reduction potentials, activating inert substrates is challenging. Recent advances in photoredox catalysis offered a number of solutions, each which useful for specific bonds. Developing general catalytic platform that can consistently target broad range would be synthetically useful. Herein, we report readily available indole thiolate organocatalyst that, upon excitation with 405 nm light, acquires strongly reducing power. This excited-state reactivity served activate, by single-electron reduction, C-F, C-Cl, C-O both aromatic aliphatic substrates. was versatile enough promote the generally recalcitrant electron-rich (Ered <-3.0 V vs SCE), including arenes afforded 1,4-cyclohexadienes. The protocol also borylation phosphorylation high functional group tolerance. Mechanistic studies identified an anion as responsible highly reactivity.

Язык: Английский

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Photoinduced activation of alkyl chlorides

Chemical Society Reviews, Год журнала: 2023, Номер 52(17), С. 6120 - 6138

Опубликована: Янв. 1, 2023

In recent years, the activation of unactivated alkyl chlorides through light-induced processes has emerged as a promising field in radical chemistry, and led to new transformations organic synthesis. Direct utilization C(sp3)-hybridized electrophiles enables facile construction carbon-carbon carbon-heteroatom bonds. Furthermore, studies medicinal chemistry indicate that their presence is associated with high levels success clinical trials. This review summarizes advances photoinduced discusses mechanistic aspects underlying these reactions. We anticipate this will serve valuable resource for researchers chemical bond functionalization, inspire considerable developments drug synthesis, materials science other related disciplines.

Язык: Английский

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Aminals as powerful XAT-reagents: activation of fluorinated alkyl chlorides

Chemical Science, Год журнала: 2023, Номер 14(12), С. 3229 - 3234

Опубликована: Янв. 1, 2023

Reagents for the activation of C–Cl bond via XAT process are described. The reaction efficiency is based on stereoelectronic effects. method applied to chlorofluorocarbons.

Язык: Английский

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Recent Advances in C–H Functionalisation through Indirect Hydrogen Atom Transfer

Molecules, Год журнала: 2023, Номер 28(16), С. 6127 - 6127

Опубликована: Авг. 18, 2023

The functionalisation of C–H bonds has been an enormous achievement in synthetic methodology, enabling new retrosynthetic disconnections and affording simple equivalents for synthons. Hydrogen atom transfer (HAT) is a key method forming alkyl radicals from substrates. Classic reactions, including the Barton nitrite ester reaction Hofmann–Löffler–Freytag reaction, among others, provided early examples HAT. However, recent developments photoredox catalysis electrochemistry have made HAT powerful tool capable introducing wide range functional groups into bonds. Moreover, greater mechanistic insights stimulated development increasingly site-selective protocols. Site-selectivity can be achieved through tuning electron density at certain using additives, judicious choice reagent, solvent system. Herein, we describe latest methods functionalizing C–H/Si–H/Ge–H indirect between 2018–2023, as well critical discussion reagents, aspects, substrate scopes, background contexts

Язык: Английский

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An Overview of α‐Aminoalkyl Radical Mediated Halogen‐Atom Transfer

ChemCatChem, Год журнала: 2023, Номер 15(21)

Опубликована: Авг. 14, 2023

Abstract The merging of photocatalysis with halogen‐atom transfer (XAT) processes has proven to be a versatile tool for the generation carbon‐centered radicals in organic synthesis. XAT are unique that they generate without requiring use strong reductants necessary traditional single electron (SET) activation halides. Pathways achieve synthetic applications can categorized into three major sections: i) heteroatom‐based activators, ii) metal‐based and iii) carbon‐based activators among which α‐aminoalkyl have taken center stage. Access these as reagents gained significant attention past few years due robustness reactions, simplicity required, broadness their applications. Generation is simply achieved through oxidation tertiary amines, after deprotonation at α‐position generates radicals. Due wide scope amines available tunable nucleophilicity radical formed, this strategy become an attractive alternative heteroatom/metal‐based XAT. In minireview, we focus our on recent (2020–2023) developments uses robust technology mediate processes.

Язык: Английский

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Aryl sulfonium salt electron donor-acceptor complexes for halogen atom transfer: Isocyanides as tunable coupling partners

Chem, Год журнала: 2024, Номер 10(4), С. 1240 - 1251

Опубликована: Фев. 13, 2024

The photoactivation of sulfonium salt EDA (electron donor-acceptor) complexes provides a mild platform for aryl-radical-mediated halogen atom transfer activation wide range functionalized alkyl iodides, including tertiary iodides. Using an aryl with carbonate as inexpensive donor complex formation, the general reaction has been applied in divergent, metal-free photochemical approach to nitriles and amides. This divergency was made possible by tuning isocyanide radical traps. For example, identification readily accessible, bench-stable, crystalline amide containing grants access nitrile products complete selectivity.

Язык: Английский

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Halogen Atom Transfer-Induced Homolysis of C–F Bonds by the Excited-State Boryl Radical

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(33), С. 22874 - 22880

Опубликована: Авг. 2, 2024

A novel reactivity toward C-F bond functionalization has been developed, which could be designated as fluorine atom transfer (FAT). photoexcited state of an

Язык: Английский

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Photoinduced Triphenylphosphine and Iodide Salt Promoted Reductive Decarboxylative Coupling

Advanced Science, Год журнала: 2024, Номер 11(12)

Опубликована: Янв. 17, 2024

Abstract The transient electron donor–acceptor (EDA) complex has been an emerging area in the photoinduced organic synthesis field, generating radicals without exogenous transition‐metal or dye‐based photoredox catalysts. catalytic platform to form suitable photoactive EDA complexes for photochemical reduction reactions remains underdeveloped. Herein, a general reductive alkylation via strategy is described. A simple yet multifunctional system, triphenylphosphine and iodide salt, promotes decarboxylative hydroalkylation, defluorinative of trifluoromethyl alkenes, access alkanes gem ‐difluoroalkenes. Moreover, hydroalkylation can be applied more kinds electron‐deficient alkenes as Giese addition reaction.

Язык: Английский

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