Selective oxidation of benzyl alcohols by silica‐supported heterogeneous catalyst containing dioxidotungsten(VI) core

Applied Organometallic Chemistry, Год журнала: 2022, Номер 37(2)

Опубликована: Окт. 22, 2022

A dioxidotungsten(VI) complex, [WO 2 L(CH 3 OH)]·0.5(CH OH) ( 1 ), was prepared by the reaction of WCl 6 and tridentate ONO‐donor Schiff base ligand H L ) that obtained from 2‐hydroxy‐1‐naphthaldehyde with 4‐aminobenzoic hydrazide. Both were characterized various analyses including nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT‐IR) UV–Vis spectroscopy, elemental analysis. Single crystal X‐ray analysis used to determine structure which revealed there is a free ‐NH group in its structure. Therefore, heterogeneous catalyst supporting on propionyl chloride‐functionalized silica gel. The synthesized supported Si‐W diffuse reflectance (DRS), thermogravimetric (TGA), FT‐IR, scanning electron microscope (SEM), photoelectron (XPS), energy‐dispersive (EDS), powder diffraction (XRD) analyses. utilized oxidation benzyl alcohol derivatives O under reflux condition at air atmosphere. effects concentration oxidant, temperature, nature solvent catalytic performance resulting compound investigated results indicated they have considerable effect activity selectivity . recovered several times reused for reaction. FT‐IR SEM, TGA, EDS, XRD are no differences between fresh one. show complex active stable benzylic alcohols depends condition.

Язык: Английский

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Exploring the potential of nanosized oxides of zinc and tin as recyclable catalytic components for the synthesis of cyclic organic carbonates under atmospheric CO2 pressure

Process Safety and Environmental Protection, Год журнала: 2023, Номер 191, С. 630 - 645

Опубликована: Фев. 7, 2023

Язык: Английский

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Alumina-Based Bifunctional Catalyst for Efficient CO₂ Fixation into Epoxides at Atmospheric Pressure

Inorganic Chemistry, Год журнала: 2022, Номер 61(41), С. 16356 - 16369

Опубликована: Окт. 4, 2022

The quest toward sustainability and decarbonization demands the development of methods for efficient carbon dioxide capture utilization. nonreductive CO2 fixation into epoxides to prepare cyclic carbonates has gained attention in recent years. In this work, we report guanidine hydrochloride-functionalized γ alumina (γ-Al2O3), prepared using green solvents, as an bifunctional catalyst fixation. resulting guanidine-grafted γ-Al2O3 (Al-Gh) proved be excellent from with high selectivity. nitrogen-rich Al-Gh shows increased adsorption capacity compared that γ-Al2O3. as-prepared was able carry out at 85 °C under atmospheric pressure absence solvents external additives (e.g., TBAI or KI). material showed negligible loss catalytic activity even after five cycles catalysis. successfully converted many their respective optimized conditions. gram-scale synthesis commercially important styrene oxide also achieved. Density functional theory (DFT) calculations revealed role activating epoxide. This activation facilitated chloride ion open ring react CO2. DFT studies validated stabilizing electron-rich intermediates during course reaction.

Язык: Английский

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Bypassing halide immobilization with cooperative polymers for the cycloaddition of atmospheric CO2 to epoxides

Chemical Engineering Journal, Год журнала: 2024, Номер unknown, С. 155635 - 155635

Опубликована: Сен. 1, 2024

Язык: Английский

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Direct coupling of CO2 with epoxides catalyzed by lanthanum(III) supported on magnetic mesoporous organosilica nanoparticles

Scientific Reports, Год журнала: 2023, Номер 13(1)

Опубликована: Апрель 4, 2023

Lanthanum(III) supported on the magnetic mesoporous organosilica nanoparticle (La@MON) has been described as an efficient, simple, and durable heterogeneous catalyst for synthesis of 5-membered cyclic carbonates from carbon dioxide (CO2) epoxides. Under optimized reaction conditions, various terminal epoxides have converted to corresponding in presence 0.3 mol% La@MON 0.5 tetrabutylammonium iodide (TBAI) co-catalyst at relatively mild conditions. It was also found that catalysts had significantly higher catalytic activity than some selected reference catalysts, which can be explained by abundance lanthanum(III) species acting Lewis acidic sites activating both epoxide molecules, along with fact channels are short provided facile mass transfer. The showed good reusability least five cycles while core helps easy separation just using external magnet.

Язык: Английский

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Samarium- and Ytterbium-Grafted Periodic Mesoporous Silica for Carbon Dioxide Capture and Conversion

Inorganic Chemistry, Год журнала: 2023, Номер 62(43), С. 17972 - 17984

Опубликована: Окт. 19, 2023

Immobilized coordination compounds of Lewis acidic metals are powerful catalytic components systems for the cycloaddition CO2 to epoxides that do not require sophisticated frameworks harness metal center and modulate its activity. Surface organometallic chemistry (SOMC) is a valuable methodology prepare well-defined site-isolated surface complexes on oxides, with ligand environments easily adjustable targeted reaction. In this work, SOMC applied SmII, YbII, SmIII alkoxide periodic mesoporous (organo)silica distinct pore symmetry/size application in The readily accessible by grafting bis(trimethylsilyl)amide precursors LnII[N(SiMe3)2]2(THF)2 (Ln = Sm, Yb) SmIII[N(SiMe3)2]3, followed exchange alcohols (ethanol neopentanol). use supports led hybrid materials relatively high areas sizes, affording good performance capture under mild conditions (60-80 °C, 1-10 bar). terms performance, recyclability, low amount added nucleophile TBAX (X Br, I), most active prepared work compare well variety previously reported SOMC-derived other heterogeneous acids displaying more elaborate environments.

Язык: Английский

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Imidazole based ionic liquid grafted graphene for enhancing the new green conversion process of carbon dioxide

Journal of Cleaner Production, Год журнала: 2023, Номер 434, С. 140083 - 140083

Опубликована: Дек. 8, 2023

Язык: Английский

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Solvent-free conversion of CO2 in carbonates through a sustainable macroporous catalyst

Giant, Год журнала: 2024, Номер 18, С. 100258 - 100258

Опубликована: Апрель 4, 2024

The novelty of this work consists synthesizing and exploiting a heterogeneous catalyst containing ammonium chloride as part the polymeric sponge sites for CO2 capture. To aim, polymerization 2-acryloyl(oxyethyl)trimethylammonium was performed in cryo-condition, presence crosslinking agent, obtaining lightweight macroporous freestanding material. Its efficiency converting aromatic aliphatic epoxides to corresponding carbonates successfully proved by using proton Nuclear Magnetic Resonance (1H-NMR). Remarkably, conversion styrene oxide (SO) carbonate (SC) reached yield 99% after 24 hours reaction. calculated versus cyclohexene is 71%. Similar results were obtained substituting resin counter anion with Br−, although kinetic slower than chloride. It worth noticing that reactions took place mixture without adding tetrabutylammonium bromide (TBAB), typically used co-catalyst convert into carbonates. recyclability as-prepared evaluated four reaction cycles, evidencing stable properties significant depletion capture efficiency. Most importantly, post-cleaning catalytic not required be reused. Finally, green chemistry metrics applied process demonstrated our approach significantly mitigates risks reduces environmental impact, thus elevating overall cleanliness proof concept.

Язык: Английский

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Magnesium-porphyrin as an efficient photocatalyst for the transformation of CO₂ to cyclic carbonates and oxazolidinones under ambient conditions

Catalysis Science & Technology, Год журнала: 2024, Номер 14(11), С. 3125 - 3130

Опубликована: Янв. 1, 2024

Herein, we report an efficient and simple photocatalytic system based on Mg-porphyrin for the synthesis of cyclic carbonates oxazolidinones. As this reaction uses non-toxic, renewable, widely available CO 2 , it promotes sustainability.

Язык: Английский

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The Catalytic Coupling of CO₂ and Glycidol toward Glycerol Carbonate

ACS Catalysis, Год журнала: 2024, Номер 14(16), С. 12454 - 12493

Опубликована: Авг. 5, 2024

Ambitious environmental objectives have driven research and innovation toward the production of biorenewable chemicals, such as glycerol carbonate. In particular, carbonate from coupling CO2 glycidol has received considerable attention chemistry chemical engineering communities. This route became particularly appealing considering that is an activated derivative glycerol, which, together with CO2, industrial waste. To keep chain value high value-added attractive possible, numerous metal-based organo-catalysts been developed. We provide this review a pragmatic overview most promising catalytic protocols reported over past 8 years. Special given to inherent mechanistic structure-(re)activity features key parameters driving reaction performances. also addresses preparation selection catalysts, well global efficiency sustainability Such holistic intended feed inspiration for future highly efficient systems.

Язык: Английский

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