Enantioselective Cobaltaphotoredox-Catalyzed C–H Activation

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(34), С. 24105 - 24113

Опубликована: Авг. 15, 2024

The quest for sustainable strategies in molecular synthesis has spurred the emergence of photocatalysis as a particularly powerful technique. In recent years, application this context greatly promoted development asymmetric catalysis. Despite impressive advances, enantioselective photoinduced strong arene C-H activations by cobalt catalysis remain unexplored. Herein, we report strategy that merges organic photoredox and cobalt-catalyzed activation, enabling regio- stereoselective dual functionalization indoles an fashion. Thereby, assembly various chiral indolo[2,3-

Язык: Английский

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Constructing a Polyoxometalate-Based Metal–Organic Framework for Photocatalytic Oxidation of Thioethers to Sulfoxides Utilizing In Situ-Generated Superoxide Radicals

Inorganic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 15, 2025

Developing new photocatalysts for the selective oxidation of thioethers to high-value-added sulfoxides under low-oxygen mild conditions is a promising but challenging strategy. Here, polyoxometalate-based metal–organic framework (POMOF), CoBW12–TPT, was successfully synthesized, wherein continuous π···π stacking interactions and direct coordination bonds not only strengthen framework's stability also accelerate electron transfer. A series experiments theoretical studies, including control experiments, kinetic electrochemical spectroscopic analyses, paramagnetic resonance, revealed synergistic catalytic effect among Co(II) metal centers, BW12O405–, photosensitizer TPT. CoBW12–TPT applied in photocatalytic sulfoxides. Under irradiation, photoinduced transfer POMOF leads generation superoxide radicals from O2, which controls sulfoxide compounds desulfurization reaction shows good activity. In particular, it can be construction some drug molecules such as Modafinil Albendazole Oxide.

Язык: Английский

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Cobalt(III)-Catalyzed Enantioselective C–H Functionalization: Ligand Innovation and Reaction Development

Accounts of Chemical Research, Год журнала: 2025, Номер unknown

Опубликована: Фев. 26, 2025

ConspectusIn contrast to precious transition metals, such as palladium and rhodium, the development of novel chiral ligands for enantioselective C-H functionalizations catalyzed by earth-abundant, cost-effective, environmentally friendly 3d metals poses substantial challenges, primarily due variable oxidation states, intricate coordination patterns, limited mechanistic insights. In this Account, we summarize our research endeavors in three types Co(III) catalysis: pseudotetrahedral achiral Cp*Co(III)/chiral carbonyl acid (CCA) catalysis, situ-generated octahedral cobalt(III) via cobalt/salicyloxazoline (Salox) Co(II)/chiral phosphoric (CPA) cooperative achieved through strategic ligand design. Our initial objective was achieve functionalization Cp*Co(III) catalysts with external ligands, aiming circumvent laborious preparation CpxCo(III) complexes. To end, developed several CCA incorporating non-covalent interactions (NCIs) a crucial design element. Next, address limitations associated lengthy synthesis Cp-ligated complexes difficulties modification, explored concept situ generation catalysis using commercially available cobalt(II) salts tailor-made ligands. This exploration led two innovative catalytic systems, namely, Co(II)/Salox Co(II)/CCA sequential catalysis. The emerged versatile strategy, demonstrating excellent enantioselectivities across range asymmetric reactions construct various molecules central, axial, planar, inherent chirality. facile single step, along ease further enhances versatility applicability approach. Moreover, successfully applied cobalt/Salox electro- photochemical-catalyzed functionalization, electrons or oxygen traceless oxidant, thereby eliminating need stoichiometric chemical oxidants. Through studies reaction developments, elucidated detailed structure-enantioselectivity relationships which are expected inform future endeavors. Finally, Co(II)/CPA enabled spiro-γ-lactams olefination/asymmetric [4 + 1] spirocyclization. Mechanistically, establishment stereochemistry occurs during cyclization where CPA serves both neutral Brønsted acid, stereoinduction independent cleavage step. We anticipate that insights advancements Account will inspire innovations drive progress metal-catalyzed reactions.

Язык: Английский

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Cobalt(II)-Catalyzed Selective C2–H Heck Reaction of Native (N–H) Indoles Enabled by Salicylaldehyde Ligand

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 8, 2025

Direct functionalization of native (N–H) indoles via C–H activation remains a challenge. Herein, we report salicylaldehyde-promoted cobalt-catalyzed selective C2–H Heck reaction with both active and unactivated olefins in the presence free N–H bonds. A series structurally diverse C2-alkenylated including natural product drug derivatives were prepared directly effectively without additional preprotection deprotection procedures.

Язык: Английский

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Atroposelective Synthesis of Pyridoindolones Bearing Two Remote Distinct C–N Axes through Cobalt-Catalyzed Enantioselective C–H Activation

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

Опубликована: Март 13, 2025

C–N axially chiral compounds represent an important class of atropisomers that are prevalent in bioactive and material molecules. Despite recent advances synthetic methodologies, the asymmetric construction featuring multiple axes has been rarely explored, significantly limiting their further applications. Herein, we report a novel atroposelective synthesis diaxially pyridoindolones both six–five six–six through cobalt-catalyzed C–H annulation. This approach demonstrates exceptional efficiency, yielding diverse array with excellent yields atroposelectivities (60 examples, up to >99% yield, ee, >20:1 dr). Mechanistic studies revealed stereochemistry were generated fixed simultaneously during cyclometalation step, along unexpected amplification effect. The practicality this protocol is underscored by successful gram-scale syntheses various transformations, including formation phosphine ligand. Notably, photoluminescence quantum (ΦF 0.99) positive solvatochromism observed, coupled significant chiroptical properties, underscoring potential applications these organic fluorescent materials.

Язык: Английский

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Highly Photoelectrical responsive and Controllable Supramolecular Helical Assemblies with Dual Functionalities as Photo-Organocatalysts

Colloids and Surfaces A Physicochemical and Engineering Aspects, Год журнала: 2025, Номер unknown, С. 136968 - 136968

Опубликована: Апрель 1, 2025

Язык: Английский

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Synergistic effects of photothermal response and Schottky junction for enhanced photothermal-assisted photocatalytic hydrogen production

Chemical Engineering Journal, Год журнала: 2025, Номер unknown, С. 162801 - 162801

Опубликована: Апрель 1, 2025

Язык: Английский

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CoNi-layered double hydroxide derived CoS2/NiS2 dodecahedron decorated with ReS2 Z-scheme heterojunction for efficient hydrogen evolution

Journal of Colloid and Interface Science, Год журнала: 2024, Номер 679, С. 21 - 30

Опубликована: Сен. 26, 2024

Язык: Английский

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