Micellar catalysis: a green solution to enable undirected and mild C–H activation of (oligo)thiophenes at the challenging β-position

Chemical Science, Год журнала: 2023, Номер 14(43), С. 12049 - 12055

Опубликована: Янв. 1, 2023

The unexpected potential of micellar medium to achieve challenging β-selective direct arylation (oligo)thiophenes is reported.

Язык: Английский

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CO₂-Triggered Hierarchical-Pore UiO-66-Based Pickering Emulsions for Efficient and Recyclable Suzuki–Miyaura Cross-Coupling in Biphasic Systems

Langmuir, Год журнала: 2023, Номер 39(42), С. 15046 - 15054

Опубликована: Окт. 9, 2023

Hierarchical-pore metal-organic frameworks (H-MOFs) are considered to be emerging stabilizers for Pickering emulsion formation because of their hierarchically arranged pores, tailorable structures, and ultrahigh surface areas. However, stimulus-triggered emulsions built by H-MOFs have been seldom presented date despite great significance in diverse applications. Herein, grafting Pd(OAc)2 on the hierarchical-pore zirconium MOF UiO-66, namely, H-UiO-66, with aid 1-alkyl-3-methylimidazolium 2-cyanopyrrolide salts ([CnMIM][2-CN-Pyr], n = 4, 6, 8), a series Pd(OAc)2-[CnMIM][2-CN-Pyr]@H-UiO-66 developed utilized as emulsifiers constructing CO2-switching emulsions. It was found that able stabilize n-hexane-water mixture form even at an amount 0.5 wt %. Upon alternate addition CO2 N2 normal pressure, could smartly converted between demulsification re-emulsification. Through combining varieties spectroscopic techniques, mechanism switchable phase transformation lay acid-base reaction ionic liquids H-UiO-66 creation more hydrophilic salts, which reduced wettability emulsifier destabilized emulsion. As example application, employed palladium-catalyzed Suzuki-Miyaura cross-coupling microreactor achieve combination chemical reactions, isolation products, recovery catalysts.

Язык: Английский

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Copper-Free Heck–Cassar–Sonogashira and Suzuki–Miyaura Reactions of Aryl Chlorides: A Sustainable Approach

ACS Sustainable Chemistry & Engineering, Год журнала: 2023, Номер 11(44), С. 15994 - 16004

Опубликована: Окт. 26, 2023

Sustainable and efficient aryl halides with copper-free Heck–Cassar–Sonogashira (HCS) Suzuki–Miyaura (SM) cross-coupling reactions were described. Independently from the chloride substituents, green protocol based on N-hydroxyethylpyrrolidone (HEP)/water as solvents sodium 2′-dicyclohexylphosphino-2,6-dimethoxy-1,1′-biphenyl-3-sulfonate (sSPhos) ligand afforded target products a high turnover number (TON), reaction mass efficiency (RME), low process intensity (PMI). The best results have been obtained TMG Cs2CO3 base for HCS K2CO3 SM coupling. PMI RME achieved are among in field allowed us to simplify purification processes that critical industrial applications.

Язык: Английский

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Key Role of Water in Copper‐ and Base‐free Sonogashira Coupling in Ethanol with [{Pd(μ‐OH)Cl(IPr)}₂] as a Highly Effective Precatalyst

ChemCatChem, Год журнала: 2024, Номер 16(13)

Опубликована: Март 18, 2024

Abstract Aryl bromides and 4‐chlorotoluene as an example aryl chloride in the presence of N ‐heterocyclic carbene (NHC) palladium hydroxo dimers type [{Pd(μ‐OH)Cl(NHC)} 2 ] (where NHC=IPr, SIPr, IMes, SIMes) undergo efficient selective Sonogashira cross‐coupling with (hetero)arylacetylenes. The procedure allows high‐throughput synthesis a broad spectrum 1,2‐diarylacetylenes using 10 ppm [{Pd(μ‐OH)Cl(IPr)} precatalyst. For coupling phenylacetylene, TON=560000 was achieved. Hydrogen observed product reaction. formation active Pd(0) from Pd(II) complex found to proceed via ethanol oxidation. Mechanistic studies showed that water plays key role

Язык: Английский

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Cross‐Coupling Between Aryl Halides and Aryl Alkynes Catalyzed by an Odd Alternant Hydrocarbon

Chemistry - A European Journal, Год журнала: 2024, Номер 30(32)

Опубликована: Апрель 8, 2024

Catalytic cross-coupling between aryl halides and alkynes is considered an extremely important organic transformation (popularly known as the Sonogashira coupling) it requires a transition metal-based catalyst. Accomplishing such without any catalyst in absence of external stimuli heat, photoexcitation or cathodic current highly challenging. This work reports transition-metal-free synthesizing rich library internal stimuli. A chemically double-reduced phenalenyl (PLY)-based molecule with super-reducing property was employed for single electron transfer to activate generating reactive radicals, which subsequently react alkyne. protocol covers not only various types aryl, heteroaryl polyaryl but also applies large variety aromatic at room temperature. With versatile substrate scope successfully tested on more than 75 entries, this radical-mediated pathway has been explained by several control experiments. All key intermediates have characterized spectroscopic evidence. Detailed DFT calculations instrumental portraying mechanistic pathway. Furthermore, we extended catalytic strategy first time towards solvent-free solid halide alkyne substrates.

Язык: Английский

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Pd-Catalyzed C(sp²)–H/C(sp²)–H Coupling of Limonene

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(15), С. 10451 - 10461

Опубликована: Июль 18, 2024

Limonene undergoes a regioselective Pd(II)-catalyzed C(sp2)–H/C(sp2)–H coupling with acrylic acid esters and amides, α,β-unsaturated ketones, styrenes, allyl acetate, affording novel 1,3-dienes. DFT computations gave results in accord the experimental allowed for formulation of plausible mechanism. The postfunctionalization one coupled products was achieved via large-scale Sonogashira reaction conducted under micellar catalysis.

Язык: Английский

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Palladium Supported on Silk Fibroin as Efficient Catalyst for Sonogashira Coupling and Sonogashira‐Cacchi Type Annulation

European Journal of Organic Chemistry, Год журнала: 2024, Номер 27(40)

Опубликована: Авг. 9, 2024

Abstract A palladium catalyst supported on silk fibroin (Pd/SF) has been tested in the Sonogashira coupling reactions of a wide range aryl iodides and terminal alkynes. The best catalytic performance was obtained at 90 °C using only 0.25 mol % metal loading under copper‐free conditions, presence H 2 O/EtOH (3 : v/v) solvent mixture triethylamine as base, affording products good yields. Pd/SF‐based protocol then successfully extended to synthesis benzofurans through Sonogashira‐Cacchi type annulation 2‐iodophenol with Preliminary investigations recyclability heterogeneous behaviour were performed: hot filtration test leaching evidenced small amount soluble active species into reaction mixture. Nevertheless, Pd/SF could be reused recharging it can recycled four consecutive runs no significant deactivation.

Язык: Английский

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Short steps synthesis of unsymmetrical acetylenes from tetrachloroethylene and arylboronic acids using Suzuki coupling reaction and improvement of mild dechlorinations

Chemistry Letters, Год журнала: 2024, Номер 53(8)

Опубликована: Июль 31, 2024

Abstract Short steps synthesis of unsymmetrical acetylenes from tetrachloroethylene and arylboronic acids, the use metal Mg as mild reagent for dechlorinations has been developed. Unsymmetrical including donor acceptor diarylacetylenes were produced in good yields. The reaction optimization, scope limitations, scale-up reaction, evaluation step studied this paper.

Язык: Английский

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Sustainable cascade reaction combining transition metal-biocatalysis and hydrophobic substrates in surfactant-free aqueous solutions

Chemical Engineering Journal, Год журнала: 2023, Номер 472, С. 144599 - 144599

Опубликована: Июль 17, 2023

Язык: Английский

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Iron-Catalyzed Carbon–Carbon Coupling Reaction

Topics in organometallic chemistry, Год журнала: 2023, Номер unknown, С. 53 - 111

Опубликована: Янв. 1, 2023

Язык: Английский

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