Bibliografías temáticas / Cycloaddition du CO2 / Artículos de revistas
Siga este enlace para ver otros tipos de publicaciones sobre el tema: Cycloaddition du CO2.

Artículos de revistas sobre el tema "Cycloaddition du CO2"

Autor: Grafiati
Publicado: 23 de noviembre de 2024

Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros

Elija tipo de fuente:

Consulte los 50 mejores artículos de revistas para su investigación sobre el tema "Cycloaddition du CO2".

Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.

También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.

Explore artículos de revistas sobre una amplia variedad de disciplinas y organice su bibliografía correctamente.

1

Krompiec, Stanisław, Aneta Kurpanik-Wójcik, Marek Matussek, Bogumiła Gołek, Angelika Mieszczanin y Aleksandra Fijołek. "Diels–Alder Cycloaddition with CO, CO2, SO2, or N2 Extrusion: A Powerful Tool for Material Chemistry". Materials 15, n.º 1 (27 de diciembre de 2021): 172. http://dx.doi.org/10.3390/ma15010172.

Texto completo
Resumen
Phenyl, naphthyl, polyarylphenyl, coronene, and other aromatic and polyaromatic moieties primarily influence the final materials’ properties. One of the synthetic tools used to implement (hetero)aromatic moieties into final structures is Diels–Alder cycloaddition (DAC), typically combined with Scholl dehydrocondensation. Substituted 2-pyranones, 1,1-dioxothiophenes, and, especially, 1,3-cyclopentadienones are valuable substrates for [4 + 2] cycloaddition, leading to multisubstituted derivatives of benzene, naphthalene, and other aromatics. Cycloadditions of dienes can be carried out with extrusion of carbon dioxide, carbon oxide, or sulphur dioxide. When pyranones, dioxothiophenes, or cyclopentadienones and DA cycloaddition are aided with acetylenes including masked ones, conjugated or isolated diynes, or polyynes and arynes, aromatic systems are obtained. This review covers the development and the current state of knowledge regarding thermal DA cycloaddition of dienes mentioned above and dienophiles leading to (hetero)aromatics via CO, CO2, or SO2 extrusion. Particular attention was paid to the role that introduced aromatic moieties play in designing molecular structures with expected properties. Undoubtedly, the DAC variants described in this review, combined with other modern synthetic tools, constitute a convenient and efficient way of obtaining functionalized nanomaterials, continually showing the potential to impact materials sciences and new technologies in the nearest future.
Los estilos APA, Harvard, Vancouver, ISO, etc.
2

Lin, Yi-Feng, Yu-Rou Lai, Hsiang-Ling Sung, Tsair-Wang Chung y Kun-Yi Andrew Lin. "Design of Amine-Modified Zr–Mg Mixed Oxide Aerogel Nanoarchitectonics with Dual Lewis Acidic and Basic Sites for CO2/Propylene Oxide Cycloaddition Reactions". Nanomaterials 12, n.º 19 (1 de octubre de 2022): 3442. http://dx.doi.org/10.3390/nano12193442.

Texto completo
Resumen
The utilization of CO2 attracts much research attention because of global warming. The CO2/epoxide cycloaddition reaction is one technique of CO2 utilization. However, homogeneous catalysts with both Lewis acidic and basic and toxic solvents, such as DMF, are needed in the CO2/epoxide cycloaddition reaction. As a result, this study focuses on the development of heterogeneous catalysts with both Lewis acidic and basic sites for the CO2 utilization of the CO2/epoxide cycloaddition reactions without the addition of a DMF toxic solvent. For the first time, the Zr–Mg mixed oxide aerogels with Lewis acidic and basic sites are synthesized for the CO2/propylene oxide (PO) cycloaddition reactions. To further increase the basic sites, 3-Aminopropyl trimethoxysilane (APTMS) with -NH2 functional group is successfully grafted on the Zr–Mg mixed oxide aerogels. The results indicate that the highest yield of propylene carbonate (PC) is 93.1% using the as-developed APTMS-modified Zr–Mg mixed oxide aerogels. The as-prepared APTMS-modified Zr–Mg mixed oxide aerogels are great potential in industrial plants for CO2 reduction in the future.
Los estilos APA, Harvard, Vancouver, ISO, etc.
3

Gao, Jie, Chengguang Yue, Hao Wang, Jiaxin Li, He Yao, Mei-Yan Wang y Xinbin Ma. "CeO2-ZrO2 Solid Solution Catalyzed and Moderate Acidic–Basic Sites Dominated Cycloaddition of CO2 with Epoxides: Halogen-Free Synthesis of Cyclic Carbonates". Catalysts 12, n.º 6 (9 de junio de 2022): 632. http://dx.doi.org/10.3390/catal12060632.

Texto completo
Resumen
For the production of cyclic carbonates from the cycloaddition of CO2 with epoxides, halogen pollution and product purity are two of the most common problems due to the usage of homogeneous halogen-containing catalysts such as ammonium salt and alkali metal halide. Hence, the development of a novel, halogen-free and efficient catalyst for the synthesis of high-purity cyclic carbonates is significant. Here, a series of acid–base bifunctional Ce1-xZrxO2 nanorods were successfully prepared. The Ce1-xZrxO2 nanorods could catalyze the cycloaddition of CO2 with epoxides efficiently without any halogen addition. Especially for the Ce0.7Zr0.3O2 catalyst, a conversion of 96% with 100% 1,2-butylene carbonate selectivity was achieved. The excellent catalytic performance of Ce1-xZrxO2 nanorods is attributed to the formation of the CeO2-ZrO2 solid solution, which contributes to abundant moderate acidic–basic active sites on the catalyst surface. It is the synergistic effect of moderate acidic–basic sites that dominates the conversion of CO2 with epoxides, which will supply important references for the synthesis of efficient metal oxide catalyst for the cycloaddition of CO2 with epoxides.
Los estilos APA, Harvard, Vancouver, ISO, etc.
4

Noh, Jinmi, Dasom Kim, Jihyun Lee, Minyoung Yoon, Myung Park, Kang Lee, Youngjo Kim y Min Kim. "Three Component Controls in Pillared Metal-Organic Frameworks for Catalytic Carbon Dioxide Fixation". Catalysts 8, n.º 11 (20 de noviembre de 2018): 565. http://dx.doi.org/10.3390/catal8110565.

Texto completo
Resumen
Three components of pillared metal-organic frameworks (MOFs, three components = metal ion, carboxylic acid ligand, and N-chelating ligand) were controlled for CO2 cycloaddition catalysts to synthesize organic cyclic carbonates. Among the divalent metals, Zn2+ showed the best catalytic activity, and in DABCO (1,4-diazabicyclo[2.2.2]octane)-based MOFs, hydroxy-functionalized DMOF-OH was the most efficient MOF for CO2 cycloaddition. For the BPY (4,4’-bipyridyl)-type MOFs, all five prepared BMOFs (BPY MOFs) showed similar and good conversions for CO2 cycloaddition. Finally, this pillared MOF could be recycled up to three times without activity and crystallinity loss.
Los estilos APA, Harvard, Vancouver, ISO, etc.
5

Shang, Shu, Wei Shao, Xiao Luo, Ming Zuo, Hui Wang, Xiaodong Zhang y Yi Xie. "Facet Engineering in Constructing Lewis Acid-Base Pairs for CO2 Cycloaddition to High Value-Added Carbonates". Research 2022 (15 de octubre de 2022): 1–9. http://dx.doi.org/10.34133/2022/9878054.

Texto completo
Resumen
Cycloaddition of epoxides with CO2 to synthesis cyclic carbonates is an atom-economic pathway for CO2 utilization with promising industry application value, while its efficiency was greatly inhibited for the lack of highly active catalytic sites. Herein, by taking BiOX (X=Cl, Br) with layered structure for example, we proposed a facet engineering strategy to construct Lewis acid-base pairs for CO2 cycloaddition, where the typical BiOBr with (010) facets expose surface Lewis acid Bi sites and Lewis base Br sites simultaneously. By the combination of in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and theoretical calculations, the oxygen atom of the epoxide is interacted with the Lewis acid Bi site to activate the ternary ring, then facilitates the attack of the carbon atom by the Lewis base Br site for the ring-opening of the epoxide, which is the rate-determining step in the cycloaddition reaction. As a result, the BiOBr-(010) with rich surface Lewis acid-base pairs showed a high conversion of 85% with 100% atomic economy in the synthesis of cyclic-carbonates without any cocatalyst. This study provides a model structure for CO2 cycloaddition to high value-added long chain chemicals.
Los estilos APA, Harvard, Vancouver, ISO, etc.
6

Kiatkittipong, Kunlanan, Muhammad Amirul Amin Mohamad Shukri, Worapon Kiatkittipong, Jun Wei Lim, Pau Loke Show, Man Kee Lam y Suttichai Assabumrungrat. "Green Pathway in Utilizing CO2 via Cycloaddition Reaction with Epoxide—A Mini Review". Processes 8, n.º 5 (8 de mayo de 2020): 548. http://dx.doi.org/10.3390/pr8050548.

Texto completo
Resumen
Carbon dioxide (CO2) has been anticipated as an ideal carbon building block for organic synthesis due to the noble properties of CO2, which are abundant renewable carbon feedstock, non-toxic nature, and contributing to a more sustainable use of resources. Several green and proficient routes have been established for chemical CO2 fixation. Among the prominent routes, this review epitomizes the reactions involving cycloaddition of epoxides with CO2 in producing cyclic carbonate. Cyclic carbonate has been widely used as a polar aprotic solvent, as an electrolyte in Li-ion batteries, and as precursors for various forms of chemical synthesis such as polycarbonates and polyurethanes. This review provides an overview in terms of the reaction mechanistic pathway and recent advances in the development of several classes of catalysts, including homogeneous organocatalysts (e.g., organic salt, ionic liquid, deep eutectic solvents), organometallic (e.g., mono-, bi-, and tri-metal salen complexes and non-salen complexes) and heterogeneous supported catalysts, and metal organic framework (MOF). Selection of effective catalysts for various epoxide substrates is very important in determining the cycloaddition operating condition. Under their catalytic systems, all classes of these catalysts, with regard to recent developments, can exhibit CO2 cycloaddition of terminal epoxide substrates at ambient temperatures and low CO2 pressure. Although highly desired conversion can be achieved for internal epoxide substrates, higher temperature and pressure are normally required. This includes fatty acid-derived terminal epoxides for oleochemical carbonate production. The production of fully renewable resources by employment of bio-based epoxy with biorefinery concept and potential enhancement of cycloaddition reactions are pointed out as well.
Los estilos APA, Harvard, Vancouver, ISO, etc.
7

Lei, Yizhu, Yali Wan, Wei Zhong, Dingfu Liu y Zhou Yang. "Phosphonium-Based Porous Ionic Polymer with Hydroxyl Groups: A Bifunctional and Robust Catalyst for Cycloaddition of CO2 into Cyclic Carbonates". Polymers 12, n.º 3 (5 de marzo de 2020): 596. http://dx.doi.org/10.3390/polym12030596.

Texto completo
Resumen
The integration of synergic hydrogen bond donors and nucleophilic anions that facilitates the ring-opening of epoxide is an effective way to develop an active catalyst for the cycloaddition of CO2 with epoxides. In this work, a new heterogeneous catalyst for the cycloaddition of epoxides and CO2 into cyclic carbonates based on dual hydroxyls-functionalized polymeric phosphonium bromide (PQPBr-2OH) was presented. Physicochemical characterizations suggested that PQPBr-2OH possessed large surface area, hierarchical pore structure, functional hydroxyl groups, and high density of active sites. Consequently, it behaved as an efficient, recyclable, and metal-free catalyst for the additive and solvent free cycloaddition of epoxides with CO2. Comparing the activity of PQPBr-2OH with that of the reference catalysts based on mono and non-hydroxyl functionalized polymeric phosphonium bromides suggested that hydroxyl functionalities in PQPBr-2OH showed a critical promotion effect on its catalytic activity for CO2 conversion. Moreover, PQPBr-2OH proved to be quite robust and recyclable. It could be reused at least ten times with only a slight decrease of its initial activity.
Los estilos APA, Harvard, Vancouver, ISO, etc.
8

Shi, Jinghua, Jinliang Song, Jun Ma, Zhaofu Zhang, Honglei Fan y Buxing Han. "Effective synthesis of cyclic carbonates from CO2 and epoxides catalyzed by KI/cucurbit[6]uril". Pure and Applied Chemistry 85, n.º 8 (4 de abril de 2013): 1633–41. http://dx.doi.org/10.1351/pac-con-12-10-09.

Texto completo
Resumen
The development of efficient, inexpensive, and nontoxic catalysts for cycloaddition of CO2 with epoxides to produce five-membered cyclic carbonates is a very interesting topic. In this work, cycloaddition of CO2 with propylene oxide (PO) to produce propylene carbonate (PC) catalyzed by potassium halides (KCl, KBr, and KI) in the presence of cucurbit[6]uril (CB[6]) was studied at various conditions. It was discovered that the potassium halides and CB[6] had excellent synergetic effect in promoting the reaction, and the KI/CB[6] catalytic system was the most efficient among them. The decrease of the activity and selectivity of KI/CB[6] was negligible after the catalytic system was reused five times. Further study indicated that the KI/CB[6] catalytic system was also very active and selective for the cycloaddition of CO2 with other epoxides, such as glycidyl phenyl ether, epichlorohydrin, and styrene oxide. The mechanism for the synergetic effect of KI and CB[6] was also discussed.
Los estilos APA, Harvard, Vancouver, ISO, etc.
9

Tangyen, Niracha, Wuttichai Natongchai y Valerio D’Elia. "Catalytic Strategies for the Cycloaddition of CO2 to Epoxides in Aqueous Media to Enhance the Activity and Recyclability of Molecular Organocatalysts". Molecules 29, n.º 10 (14 de mayo de 2024): 2307. http://dx.doi.org/10.3390/molecules29102307.

Texto completo
Resumen
The cycloaddition of CO2 to epoxides to afford versatile and useful cyclic carbonate compounds is a highly investigated method for the nonreductive upcycling of CO2. One of the main focuses of the current research in this area is the discovery of readily available, sustainable, and inexpensive catalysts, and of catalytic methodologies that allow their seamless solvent-free recycling. Water, often regarded as an undesirable pollutant in the cycloaddition process, is progressively emerging as a helpful reaction component. On the one hand, it serves as an inexpensive hydrogen bond donor (HBD) to enhance the performance of ionic compounds; on the other hand, aqueous media allow the development of diverse catalytic protocols that can boost catalytic performance or ease the recycling of molecular catalysts. An overview of the advances in the use of aqueous and biphasic aqueous systems for the cycloaddition of CO2 to epoxides is provided in this work along with recommendations for possible future developments.
Los estilos APA, Harvard, Vancouver, ISO, etc.
10

Bester, Karol, Agnieszka Bukowska, Aleksandra Kawka, Maciej Pytel y Wiktor Bukowski. "Salophen chromium(iii) complexes functionalized with pyridinium salts as catalysts for carbon dioxide cycloaddition to epoxides". RSC Advances 14, n.º 4 (2024): 2466–80. http://dx.doi.org/10.1039/d3ra07750k.

Texto completo
Resumen
Novel multifunctional one-component catalysts for the cycloaddition of CO2 to epoxides. The selective and effective conversion of substrates to cyclic carbonates possible using 0.01 mol% catalyst and a low CO2 pressure.
Los estilos APA, Harvard, Vancouver, ISO, etc.
11

Cheng, Weiwei, Yun-shan Xue, Xi-Ming Luo y Yan Xu. "A rare three-dimensional POM-based inorganic metal polymer bonded by CO2 with high catalytic performance for CO2 cycloaddition". Chemical Communications 54, n.º 91 (2018): 12808–11. http://dx.doi.org/10.1039/c8cc07041e.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
12

Sengoden, Mani, Gulzar A. Bhat y Donald J. Darensbourg. "Bifunctional organoboron–phosphonium catalysts for coupling reactions of CO2 and epoxides". RSC Advances 12, n.º 50 (2022): 32440–47. http://dx.doi.org/10.1039/d2ra06358a.

Texto completo
Resumen
A series of organoborane phosphonium salts have been shown to be very effective catalysts for the copolymerization of alicyclic epoxides with CO2 or the cycloaddition of aliphatic epoxides and CO2 to afford polycarbonates or cyclic carbonates, respectively.
Los estilos APA, Harvard, Vancouver, ISO, etc.
13

Cormier, Morgan, Eric Fouquet y Philippe Hermange. "Expedient synthesis of a symmetric cycloheptyne-Co2(CO)6 complex for orthogonal Huisgen cycloadditions". Organic Chemistry Frontiers 6, n.º 8 (2019): 1114–17. http://dx.doi.org/10.1039/c9qo00086k.

Texto completo
Resumen
A cycloheptyne dicobalt-carbonyl complex with a terminal alkyne was synthesized by a short procedure, and was able to react selectively in Strain Promoted Alkyne Azide Cycloaddition (SPAAC) or Copper Catalysed Alkyne Azide Cycloaddition (CuAAC) depending on the conditions.
Los estilos APA, Harvard, Vancouver, ISO, etc.
14

Gu, Yunjang, Youngson Choe y Dae-Won Park. "Catalytic Performance of CPM-200-In/Mg in the Cycloaddition of CO2 and Epoxides". Catalysts 11, n.º 4 (27 de marzo de 2021): 430. http://dx.doi.org/10.3390/catal11040430.

Texto completo
Resumen
Crystalline porous materials (CPM)-200-In and CPM-200-In/Mg metal-organic frameworks (MOFs) were synthesized by a solvothermal method and were characterized by using powder X-ray diffraction (PXRD), FT-IR, Brunauer–Emmett–Teller (BET), temperature programmed desorption (TPD), TGA, XPS, and SEM-EDS. They were used as heterogeneous catalysts for the cycloaddition of CO2 with epoxides and found to be highly efficient toward the cycloaddition reaction at moderate reaction conditions under solvent-free conditions. The catalyst was easily separated by a simple filtration and can be reused up to five consecutive times without any considerable decrease of its initial activity. CPM-200-In/Mg showed excellent catalytic performance in the cycloaddition reaction due to the synergistic role of the acidic sites and basic sites. A plausible reaction mechanism for the CPM-200-In/Mg MOF catalyzed cycloaddition reaction is proposed based on the experimental results and our previously reported DFT (Density Functional Theory) studies.
Los estilos APA, Harvard, Vancouver, ISO, etc.
15

Akimana, Emmanuelia, Jichao Wang, Natalya V. Likhanova, Somboon Chaemchuen y Francis Verpoort. "MIL-101(Cr) for CO2 Conversion into Cyclic Carbonates, Under Solvent and Co-Catalyst Free Mild Reaction Conditions". Catalysts 10, n.º 4 (22 de abril de 2020): 453. http://dx.doi.org/10.3390/catal10040453.

Texto completo
Resumen
Mild reaction conditions (nearly room temperature and atmospheric CO2 pressure) for the cycloaddition of CO2 with epoxides to produce cyclic carbonates were investigated applying MIL-101(Cr) as a catalyst. The MIL-101 catalyst contains strong acid sites, which promote the ring-opening of the epoxide substrate. Moreover, the high surface area, enabling the adsorption of more CO2 (substrate), combined with a large pore size of the catalyst is essential for the catalytic performance. Additionally, epoxide substrates bearing electron-withdrawing substituents or having a low boiling point demonstrated an excellent conversion towards the cyclic carbonates. MIL-101(Cr) for the cycloaddition of carbon dioxide with epoxides is demonstrated to be a robust and stable catalyst able to be re-used at least five times without loss in activity.
Los estilos APA, Harvard, Vancouver, ISO, etc.
16

Yang, Chaokun, Xin Zhao y Tuantuan Yang. "Boron and Phosphorus Co-Doped Graphitic Carbon Nitride Cooperate with Bu4NBr as Binary Heterogeneous Catalysts for the Cycloaddition of CO2 to Epoxides". Catalysts 12, n.º 10 (8 de octubre de 2022): 1196. http://dx.doi.org/10.3390/catal12101196.

Texto completo
Resumen
The development of a cost-effective heterogeneous catalytic system for the cycloaddition reaction of CO2 and epoxides is of great importance. In this manuscript, three kinds of boron and phosphorus co-doping graphitic carbon nitride (BP-CN) were prepared and characterized. Among them, BP-CN-1 displayed the optimal catalytic performance in the presence of Bu4NBr (tetrabutylammonium bromide) for the CO2 cycloaddition with propylene oxide, and 95% propylene carbonate yield was obtained under a 120 °C, 2 MPa, 6 h condition. Moreover, the BP-CN-1/Bu4NBr catalytic system is compatible with various epoxides and also exhibits excellent recycling performance under metal- and solvent-free conditions. Hence, BP-CN-1 exhibited an attractive application for the efficient fixation of CO2 due to the simple, eco-friendly synthesis route and effective catalytic activity.
Los estilos APA, Harvard, Vancouver, ISO, etc.
17

Lin, Xiu-Zhen, Zhen-Zhen Yang, Liang-Nian He y Zhong-Yong Yuan. "Mesoporous zirconium phosphonates as efficient catalysts for chemical CO2 fixation". Green Chemistry 17, n.º 2 (2015): 795–98. http://dx.doi.org/10.1039/c4gc01709a.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
18

Kolle, Joel M. y Abdelhamid Sayari. "Novel porous organocatalysts for cycloaddition of CO2 and epoxides". RSC Advances 9, n.º 42 (2019): 24527–38. http://dx.doi.org/10.1039/c9ra05466a.

Texto completo
Resumen
Three classes of organosilicas (DMO, OMOs and PMOs) containing multi-hydroxyl bis-quaternary ammonium iodide were tested in the cycloaddition of CO2 and epoxides. OMO with two hydroxyl groups was the most active, with good stable and reusability.
Los estilos APA, Harvard, Vancouver, ISO, etc.
19

An, Changwei, Jun Zhang y Xianqi Guan. "CO2 Adsorption Based on Porphyrin Based Porous Organic Polymers". Journal of Physics: Conference Series 2463, n.º 1 (1 de marzo de 2023): 012057. http://dx.doi.org/10.1088/1742-6596/2463/1/012057.

Texto completo
Resumen
Abstract In order to efficiently catalyze the cycloaddition reaction of CO2 and epoxy alkanes under mild environment and no catalyst, this paper designed and synthesized two kinds of porphyrin based porous organic polymers—porphyrin based porous organic polymer containing carboxyl group (ppop-cooh) and porphyrin based porous organic polymer containing quaternary ammonium salt ion pair. Quaternary ammonium salt cation anion pair nucleophilic groups and metal active centers were introduced into the polymer by pre- and post-modification respectively. The chemical structure and pore structure of the polymer were characterized by infrared spectroscopy and physical adsorption instrument, and its effect as a catalyst on the cycloaddition reaction of CO2 and epoxy alkanes was studied. From the results, it is demonstrated that the two polymers had a multistage pore structure with a specific surface area of 302 m2/g-514 m2/g. The synergistic effect of Lewis acid metal ions, nucleophiles and multistage pore structure in the polymer significantly promotes the cycloaddition reaction between CO2 and epoxy alkanes. Under mild conditions (80°C, 0.3 MPa, 24h), the selectivity and conversion of the reaction reach more than 99%. The polymer is repeated for many times. After use, it still has good catalytic performance.
Los estilos APA, Harvard, Vancouver, ISO, etc.
20

Chen, Ying, Yingjun Li, Hu Wang, Zaifei Chen y Yi-Zhu Lei. "Facile Construction of Carboxyl-Functionalized Ionic Polymer towards Synergistic Catalytic Cycloaddition of Carbon Dioxide into Cyclic Carbonates". International Journal of Molecular Sciences 23, n.º 18 (17 de septiembre de 2022): 10879. http://dx.doi.org/10.3390/ijms231810879.

Texto completo
Resumen
The development of bifunctional ionic polymers as heterogeneous catalysts for effective, cocatalyst- and metal-free cycloaddition of carbon dioxide into cyclic carbonates has attracted increasing attention. However, facile fabrication of such polymers having high numbers of ionic active sites, suitable types of hydrogen bond donors (HBDs), and controlled spatial positions of dual active sites remains a challenging task. Herein, imidazolium-based ionic polymers with hydroxyl/carboxyl groups and high ionic density were facilely prepared by a one-pot quaternization reaction. Catalytic evaluation demonstrated that the presence of HBDs (hydroxyl or carboxyl) could enhance the catalytic activities of ionic polymers significantly toward the CO2 cycloaddition reaction. Among the prepared catalysts, carboxyl-functionalized ionic polymer (PIMBr-COOH) displayed the highest catalytic activity (94% yield) in the benchmark cycloaddition reaction of CO2 and epichlorohydrin, which was higher than hydroxyl-functionalized ionic polymer (PIMBr-OH, 76% yield), and far exceeded ionic polymer without HBDs groups (PIMBr, 54% yield). Furthermore, PIMBr-COOH demonstrated good recyclability and wide substrate tolerance. Under ambient CO2 pressure, a number of epoxides were smoothly cycloadded into cyclic carbonates. Additionally, density functional theory (DFT) calculation verified the formation of strong hydrogen bonds between epoxide and the HBDs of ionic polymers. Furthermore, a possible mechanism was proposed based on the synergistic effect between carboxyl and Br− functionalities. Thus, a facile, one-pot synthetic strategy for the construction of bifunctional ionic polymers was developed for CO2 fixation.
Los estilos APA, Harvard, Vancouver, ISO, etc.
21

Zhang, Wuying, Qian He, Yaju Chen, Rongchang Luo, Xiantai Zhou y Hongbing Ji. "A metal-free hydroxyl functionalized quaternary phosphine type ionic liquid polymer for cycloaddition of CO2 and epoxides". Dalton Transactions 51, n.º 4 (2022): 1303–7. http://dx.doi.org/10.1039/d1dt03232a.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
22

Appaturi, Jimmy Nelson, Rajabathar Jothi Ramalingam, Muthu Kumaran Gnanamani, Govindasami Periyasami, Prabhakarn Arunachalam, Rohana Adnan, Farook Adam, Mohammed D. Wasmiah y Hamad A. Al-Lohedan. "Review on Carbon Dioxide Utilization for Cycloaddition of Epoxides by Ionic Liquid-Modified Hybrid Catalysts: Effect of Influential Parameters and Mechanisms Insight". Catalysts 11, n.º 1 (23 de diciembre de 2020): 4. http://dx.doi.org/10.3390/catal11010004.

Texto completo
Resumen
The storage, utilization, and control of the greenhouse (CO2) gas is a topic of interest for researchers in academia and society. The present review article is dedicating to cover the overall role of ionic liquid-modified hybrid materials in cycloaddition reactions. Special emphasis is on the synthesis of various cyclic carbonate using ionic liquid-based modified catalysts. Catalytic activity studies have discussed with respect to process conditions and their effects on conversion and product selectivity for the reaction of cycloaddition of CO2 with styrene oxide. The reaction temperature and the partial pressure of CO2 have found to play a key role in cyclic carbonate formation. The role of other influential parameter (solvent effect) is also discussed for the conversion of cyclic/aromatic oxides to polycarbonate production. Our own research work that deals with ionic liquid-based halide-modified mesoporous catalyst (MCM-41 type) derived from rice husk waste has also been discussed. Finally, the role of carbon dioxide activation and ring-opening mechanisms involved in the cyclic carbonate product formation from CO2 have been discussed.
Los estilos APA, Harvard, Vancouver, ISO, etc.
23

Kim, Jun, Se-Na Kim, Hoi-Gu Jang, Gon Seo y Wha-Seung Ahn. "CO2 cycloaddition of styrene oxide over MOF catalysts". Applied Catalysis A: General 453 (febrero de 2013): 175–80. http://dx.doi.org/10.1016/j.apcata.2012.12.018.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
24

Shao, Dan, Jinbiao Shi, Jianling Zhang, Xiuniang Tan, Tian Luo, Xiuyan Cheng, Bingxing Zhang y Buxing Han. "Solvent Impedes CO2 Cycloaddition on Metal-Organic Frameworks". Chemistry - An Asian Journal 13, n.º 4 (29 de enero de 2018): 386–89. http://dx.doi.org/10.1002/asia.201701706.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
25

Qaroush, Abdussalam K., Areej K. Hasan, Suhad B. Hammad, Feda’a M. Al-Qaisi, Khaleel I. Assaf, Fatima Alsoubani y Ala’a F. Eftaiha. "Mechanistic insights on CO2 utilization using sustainable catalysis". New Journal of Chemistry 45, n.º 47 (2021): 22280–88. http://dx.doi.org/10.1039/d1nj04757d.

Texto completo
Resumen
Caffeinium halides were used to catalyse the cycloaddition of CO2 to form cyclic carbonates. The reaction intermediates were isolated and characterized experimentally. The reaction mechanism has been confirmed by DFT calculations.
Los estilos APA, Harvard, Vancouver, ISO, etc.
26

Borah, Rakhimoni, Surabhi Lahkar, Naranarayan Deori y Sanfaori Brahma. "Synthesis, characterization and application of oxovanadium(iv) complexes with [NNO] donor ligands: X-ray structures of their corresponding dioxovanadium(v) complexes". RSC Advances 12, n.º 22 (2022): 13740–48. http://dx.doi.org/10.1039/d2ra01448c.

Texto completo
Resumen
Oxovanadium(iv) complexes catalysed CO2 cycloaddition resulting up to 100% conversion of epoxides to cyclic carbonates under relatively benign condition. Transformation of oxovanadium(iv) to dioxovanadium(v) in the process of crystallization.
Los estilos APA, Harvard, Vancouver, ISO, etc.
27

Houbben, Maxime, Jean-Michel Thomassin y Christine Jérôme. "Supercritical CO2 blown poly(ε-caprolactone) covalent adaptable networks towards unprecedented low density shape memory foams". Materials Advances 3, n.º 6 (2022): 2918–26. http://dx.doi.org/10.1039/d2ma00040g.

Texto completo
Resumen
Supercritical CO2 blown foams of poly(ε-caprolactone) (PCL) covalent networks are developed through a two-step strategy by taking advantage of the thermo-reversible Diels–Alder cycloaddition between furan and maleimide.
Los estilos APA, Harvard, Vancouver, ISO, etc.
28

Guiducci, Aldo E., Catherine L. Boyd, Eric Clot y Philip Mountford. "Reactions of cyclopentadienyl-amidinate titanium imido compounds with CO2: cycloaddition-extrusion vs. cycloaddition-insertion". Dalton Transactions, n.º 30 (2009): 5960. http://dx.doi.org/10.1039/b901774g.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
29

Qaroush, Abdussalam K., Fatima A. Alsoubani, Ala'a M. Al-Khateeb, Enas Nabih, Esraa Al-Ramahi, Mohammad F. Khanfar, Khaleel I. Assaf y Ala'a F. Eftaiha. "An efficient atom-economical chemoselective CO2 cycloaddition using lanthanum oxide/tetrabutyl ammonium bromide". Sustainable Energy & Fuels 2, n.º 6 (2018): 1342–49. http://dx.doi.org/10.1039/c8se00092a.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
30

Gao, Aijia, Fangfang Li, Zhi Xu, Changchun Ji, Jing Gu y Ying-Hua Zhou. "Guanidyl-implanted UiO-66 as an efficient catalyst for the enhanced conversion of carbon dioxide into cyclic carbonates". Dalton Transactions 51, n.º 6 (2022): 2567–76. http://dx.doi.org/10.1039/d1dt04110j.

Texto completo
Resumen
The guanidyl-modified UiO-66 exhibited great activity for epoxide-CO2 cycloaddition with Bu4NBr cocatalyst, attributed to the synergistic effect of guanidyl groups as hydrogen-bond donors and Zr centers as Lewis-acidic sites.
Los estilos APA, Harvard, Vancouver, ISO, etc.
31

Lv, Hongxiao, Liming Fan, Hongtai Chen, Xiutang Zhang y Yanpeng Gao. "Nanochannel-based {BaZn}–organic framework for catalytic activity on the cycloaddition reaction of epoxides with CO2 and deacetalization-Knoevenagel condensation". Dalton Transactions 51, n.º 9 (2022): 3546–56. http://dx.doi.org/10.1039/d1dt04231a.

Texto completo
Resumen
Nanochannel-based {[(CH3)2NH2]2[BaZn(TDP)(H2O)]×DMF×5H2O}n (NUC-51) is synthesized and displays a high catalytic activity on the cycloaddition reactions of epoxides with CO2 and the deacetalization-Knoevenagel condensation reaction.
Los estilos APA, Harvard, Vancouver, ISO, etc.
32

Zhang, Xiao, Yan-Zong Lv, Xiao-Liang Liu, Guo-Jing Du, Shi-Hao Yan, Jian Liu y Zhen Zhao. "A hydroxyl-functionalized microporous organic polymer for capture and catalytic conversion of CO2". RSC Advances 6, n.º 80 (2016): 76957–63. http://dx.doi.org/10.1039/c6ra10780j.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
33

Wang, Yanyan, Shaopeng Li, Youdi Yang, Xiaojun Shen, Huizhen Liu y Buxing Han. "A fully heterogeneous catalyst Br-LDH for the cycloaddition reactions of CO2 with epoxides". Chemical Communications 55, n.º 48 (2019): 6942–45. http://dx.doi.org/10.1039/c9cc03052b.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
34

Alkordi, Mohamed H., Łukasz J. Weseliński, Valerio D'Elia, Samir Barman, Amandine Cadiau, Mohamed N. Hedhili, Amy J. Cairns, Rasha G. AbdulHalim, Jean-Marie Basset y Mohamed Eddaoudi. "CO2conversion: the potential of porous-organic polymers (POPs) for catalytic CO2–epoxide insertion". Journal of Materials Chemistry A 4, n.º 19 (2016): 7453–60. http://dx.doi.org/10.1039/c5ta09321j.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
35

Helal, Aasif, Kyle E. Cordova, Md Eyasin Arafat, Muhammad Usman y Zain H. Yamani. "Defect-engineering a metal–organic framework for CO2 fixation in the synthesis of bioactive oxazolidinones". Inorganic Chemistry Frontiers 7, n.º 19 (2020): 3571–77. http://dx.doi.org/10.1039/d0qi00496k.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
36

Krafft, Marie E., James A. Wright y Llorente VR Boñaga. "Pauson–Khand reactions in water". Canadian Journal of Chemistry 83, n.º 6-7 (1 de junio de 2005): 1006–16. http://dx.doi.org/10.1139/v05-112.

Texto completo
Resumen
We have investigated the cobalt mediated Pauson–Khand (PK) reaction in water. In the presence of detergents and surfactants, Co2(CO)8 and Co4(CO)12 are effective under aqueous-phase, thermal PK reactions. In a water–Triton®X-100 medium, Co4(CO)12 is catalytically active. Further, dicobalthexacarbonyl complexes of alkynes and enynes undergo effective cyclization under thermal (70 °C) and NMO-promoted conditions. The oxidative nature of the latter conditions inhibits the reductive PK reaction. In all protocols, moderate to excellent yields of the cycloadducts are obtained. Substrates that are prone to hydrolysis, such as acetals, highly activated carboxylic acid derivatives, and those bearing propargylic heteroatom groups are tolerated under appropriate conditions. Finally, the more challenging intermolecular cycloadditions can also be easily achieved under aqueous conditions.Key words: alkyne, cycloaddition, green chemistry, Pauson–Khand reaction, water.
Los estilos APA, Harvard, Vancouver, ISO, etc.
37

Xu, Cong, Yan Liu, Li Wang, Jingxin Ma, Lizi Yang, Fu-Xin Pan, Alexander M. Kirillov y Weisheng Liu. "New lanthanide(iii) coordination polymers: synthesis, structural features, and catalytic activity in CO2 fixation". Dalton Transactions 46, n.º 47 (2017): 16426–31. http://dx.doi.org/10.1039/c7dt03574h.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
38

Zhang, Xiaofei, Haitao Liu, Pengfei An, Yanan Shi, Jianyu Han, Zhongjie Yang, Chang Long et al. "Delocalized electron effect on single metal sites in ultrathin conjugated microporous polymer nanosheets for boosting CO2 cycloaddition". Science Advances 6, n.º 17 (abril de 2020): eaaz4824. http://dx.doi.org/10.1126/sciadv.aaz4824.

Texto completo
Resumen
CO2 cycloaddition with epoxides at low temperature and pressure has been broadly recognized as an ambitious but challenging goal, which requires the catalysts to have precisely controlled Lewis acid sites. Here, we demonstrate that both stereochemical environment and oxidation state of single cobalt active sites in cobalt tetraaminophthalocyanine [CoPc(NH2)4] are finely tuned via molecular engineering with 2,5-di-tert-butyl-1,4-benzoquinone (DTBBQ). Notably, DTBBQ incorporation not only enables formation of 5-nm-thick conjugated microporous polymer (CMP) nanosheets due to the steric hindrance effect of tert-butyl groups but also makes isolated cobalt sites with high oxidation state due to the presence of delocalized electron-withdrawing effect of alkene groups in DTBBQ via conjugated skeleton. Notably, when used as heterogeneous catalysts for CO2 cycloaddition with different epoxides, single cobalt active sites on the ultrathin CMP nanosheets exhibit unprecedentedly high activity and excellent stability under mild reaction conditions.
Los estilos APA, Harvard, Vancouver, ISO, etc.
39

Yue, Shuang, Qian Song, Shuliang Zang, Guichun Deng y Jun Li. "Amino-Functional Ionic Liquids as Efficient Catalysts for the Cycloaddition of Carbon Dioxide to Yield Cyclic Carbonates: Catalytic and Kinetic Investigation". Australian Journal of Chemistry 71, n.º 6 (2018): 407. http://dx.doi.org/10.1071/ch17656.

Texto completo
Resumen
Various amino-functional ionic liquids were developed as homogeneous catalysts for the cycloaddition of carbon dioxide to different epoxides yielding the corresponding cyclic carbonates under metal- and solvent-free conditions. The effects of reaction temperature, reaction time, CO2 pressure, and the amount of catalyst on the cycloaddition reaction were investigated. The catalysts could be easily recovered after the reaction and then reused at least eight times without noticeable loss of activity and selectivity. Reaction kinetic studies were undertaken, the reaction was apparently first order with respect to the concentration of epoxide and catalyst. Furthermore, the rate constants were determined over a temperature range of 100–130°C and the activation energy was determined to be 45.9 kJ mol−1. Finally, a possible reaction mechanism was proposed. The amino-functional ionic liquids showed the advantage of high catalytic activity and were easily recyclable for CO2 chemical fixation into valuable chemicals.
Los estilos APA, Harvard, Vancouver, ISO, etc.
40

Ghosh, Anindya, G. Naaresh Reddy, Mohammed Siddhique P. K., Sauvik Chatterjee, Sudip Bhattacharjee, Rahul Maitra, Sergey E. Lyubimov et al. "Fabrication of a hollow sphere N,S co-doped bifunctional carbon catalyst for sustainable fixation of CO2 to cyclic carbonates". Green Chemistry 24, n.º 4 (2022): 1673–92. http://dx.doi.org/10.1039/d1gc04153c.

Texto completo
Resumen
Compositional doping by nitrogen and sulfur into a carbon matrix with a distinct hollow sphere architecture was achieved via a simple approach and the co-doped carbon material was used as a bifunctional catalyst for an efficient CO2–epichlorohydrin cycloaddition reaction.
Los estilos APA, Harvard, Vancouver, ISO, etc.
41

Li, Shuqing, Zhen Zhan, Xiaoyan Wang y Bien Tan. "Synthesis of hypercrosslinked polymers spherical shell for highly effective cycloaddition of CO2 at ambient conditions". Polymer Chemistry, 2023. http://dx.doi.org/10.1039/d3py00649b.

Texto completo
Resumen
CO2 cycloaddition conversion is a promising strategy for converting CO2 into high-value-added products. However, most of the research focused on CO2 cycloaddition conversion under high temperature and/or pressure conditions. The...
Los estilos APA, Harvard, Vancouver, ISO, etc.
42

Gao, Bohai, Weijie Li, Yuchao Chai, Guangjun Wu y Landong Li. "Heteroatom‐Containing Zeolites as Solid Lewis Acid Catalysts for the Cycloaddition of CO2 to Epoxides". ChemCatChem, 8 de septiembre de 2024. http://dx.doi.org/10.1002/cctc.202401385.

Texto completo
Resumen
The catalytic cycloaddition of CO2 to epoxides to produce valuable cyclic carbonates represents a simple and promising strategy for CO2 utilization, circumventing the ineffective CO2 reduction process. Despite current progresses, there remains an impending demand for highly‐active, cost‐effective and stable catalysts especially the ideal heterogeneous catalytic systems. Herein, we report the preparation of heteroatom‐containing zeolites through a two‐step process comprising of framework dealumination and subsequent heteroatom incorporation, and their catalytic applications in CO2 cycloaddition to epoxides. Characterization results reveal the successful incorporation of heteroatoms into framework to derive Lewis acidic M‐Beta zeolites (M=Ti, Zr or Hf). The as‐prepared M‐Beta Lewis acids show remarkable performance in the model reaction of CO2 cycloaddition to propylene oxide with the assistance of potassium iodide under solvent‐free conditions. The reaction parameters have been optimized employing Ti‐Beta catalyst and the substrate scope has been investigated. Finally, the impact of Lewis acidity on the cycloaddition reaction is discussed and the actual bifunctional Ti‐Beta/KI catalyst system is proposed, which is of important significance for the understanding of CO2 catalytic cycloaddition to epoxides.
Los estilos APA, Harvard, Vancouver, ISO, etc.
43

Kaewsai, Suthida, Silvano Del Gobbo y Valerio D'Elia. "Synthesis of Bifunctional Catalysts for the Cycloaddition of CO2 to Epoxides through an Epoxide‐driven Strategy". ChemCatChem, 7 de febrero de 2024. http://dx.doi.org/10.1002/cctc.202301713.

Texto completo
Resumen
The design of molecular scaffolds bearing multiple functional groups for the activation and ring‐opening of epoxides is a crucial challenge for the synthesis of efficient homogeneous and heterogeneous catalysts for the cycloaddition reaction of CO2 to epoxides. Traditional approaches to prepare such multifunctional catalysts often imply multistep synthetic procedures and expensive building blocks. In this work we show that bifunctional catalysts for the cycloaddition of CO2 to epoxides bearing a Lewis acid metal and a quaternary ammonium halide group can be prepared in just two steps starting from an opportunely designed epoxide precursor by using inexpensive substrates. Such a readily accessible catalyst was applied for the cycloaddition of CO2 to a series of epoxides under atmospheric conditions generally leading to quantitative substrate conversion and high carbonate selectivities. Importantly, we also show that the epoxide‐driven concept developed for the preparation of the molecular catalyst, could be applied to prepare recyclable heterogeneous systems for the target cycloaddition reaction.
Los estilos APA, Harvard, Vancouver, ISO, etc.
44

Zhou, Minghui, Zhengyan Qu, Jiuxuan Zhang, Hong Jiang, Zhenchen Tang y Rizhi Chen. "Boosting CO2 chemical fixation over MOF-808 by introduction of functional groups and defective Zr sites". Chemical Communications, 2024. http://dx.doi.org/10.1039/d3cc06154j.

Texto completo
Resumen
The CO2 cycloaddition emerges as a promising approach for producing value-added cyclocarbonates and mitigating of greenhouse gas emissions. Although MOF-808 serves as a stable catalyst for cycloaddition, its limited activity...
Los estilos APA, Harvard, Vancouver, ISO, etc.
45

Yu, Wen-Wang, Xiang-Guang Meng, Zi-Yu Gan, Wen Li, Yu-Lian Zhang y Jie Zhou. "Cycloaddition of CO2 with epoxides into cyclic carbonates catalyzed by binary organocatalyst under mild conditions". Catalysis Science & Technology, 2024. http://dx.doi.org/10.1039/d4cy00639a.

Texto completo
Resumen
Fixing CO2 into value-added cyclic carbonates is an effective way to reduce CO2 emissions. A metal-free and solvent-free catalytic system has been developed for the cycloaddition of CO2 with epoxides...
Los estilos APA, Harvard, Vancouver, ISO, etc.
46

Wang, Yifan, Huimin Liu, Qiujin Shi, Zerui Miao, Haohong Duan, Yiou Wang, Hongpan Rong y Jiatao Zhang. "Single‐Atom Titanium on Mesoporous Nitrogen, Oxygen‐Doped Carbon for Efficient Photo‐thermal Catalytic CO2 Cycloaddition by a Radical Mechanism". Angewandte Chemie International Edition, 6 de abril de 2024. http://dx.doi.org/10.1002/anie.202404911.

Texto completo
Resumen
Developing efficient and earth‐abundant catalysts for CO2 fixation to high value‐added chemicals is meaningful but challenging. Styrene carbonate has great market value, but the cycloaddition of CO2 to styrene oxide is difficult due to the high steric hindrance and weak electron‐withdrawing ability of the phenyl group. To utilize clean energy (such as optical energy) directly and effectively for CO2 value‐added process, we introduce earth‐abundant Ti single‐atom into the mesoporous nitrogen, oxygen‐doped carbon nanosheets (Ti‐CNO) by a two‐step method. The Ti‐CNO exhibits excellent photothermal catalytic activities and stability for cycloaddition of CO2 and styrene oxide to styrene carbonate. Under light irradiation and ambient pressure, an optimal Ti‐CNO produces styrene carbonate with a yield of 98.3%, much higher than CN (27.1%). In addition, it shows remarkable stability during 10 consecutive cycles. Its enhanced catalytic performance stems from the enhanced photothermal effect and improved Lewis acidic/basic sites exposed by the abundant mesopores. The experiments and theoretical simulations demonstrate the styrene oxide•+ and CO2•‐ radicals generated at the Lewis acidic (Tiδ+) and basic sites of Ti‐CNO under light irradiation, respectively. This work furnishes a strategy for synthesizing advanced single‐atom catalysts for photo‐thermal synergistic CO2 fixation to high value products via a cycloaddition pathway.
Los estilos APA, Harvard, Vancouver, ISO, etc.
47

Wang, Yifan, Huimin Liu, Qiujin Shi, Zerui Miao, Haohong Duan, Yiou Wang, Hongpan Rong y Jiatao Zhang. "Single‐Atom Titanium on Mesoporous Nitrogen, Oxygen‐Doped Carbon for Efficient Photo‐thermal Catalytic CO2 Cycloaddition by a Radical Mechanism". Angewandte Chemie, 6 de abril de 2024. http://dx.doi.org/10.1002/ange.202404911.

Texto completo
Resumen
Developing efficient and earth‐abundant catalysts for CO2 fixation to high value‐added chemicals is meaningful but challenging. Styrene carbonate has great market value, but the cycloaddition of CO2 to styrene oxide is difficult due to the high steric hindrance and weak electron‐withdrawing ability of the phenyl group. To utilize clean energy (such as optical energy) directly and effectively for CO2 value‐added process, we introduce earth‐abundant Ti single‐atom into the mesoporous nitrogen, oxygen‐doped carbon nanosheets (Ti‐CNO) by a two‐step method. The Ti‐CNO exhibits excellent photothermal catalytic activities and stability for cycloaddition of CO2 and styrene oxide to styrene carbonate. Under light irradiation and ambient pressure, an optimal Ti‐CNO produces styrene carbonate with a yield of 98.3%, much higher than CN (27.1%). In addition, it shows remarkable stability during 10 consecutive cycles. Its enhanced catalytic performance stems from the enhanced photothermal effect and improved Lewis acidic/basic sites exposed by the abundant mesopores. The experiments and theoretical simulations demonstrate the styrene oxide•+ and CO2•‐ radicals generated at the Lewis acidic (Tiδ+) and basic sites of Ti‐CNO under light irradiation, respectively. This work furnishes a strategy for synthesizing advanced single‐atom catalysts for photo‐thermal synergistic CO2 fixation to high value products via a cycloaddition pathway.
Los estilos APA, Harvard, Vancouver, ISO, etc.
48

Sharma, Neha, Bharat Ugale, Sunil Kumar y Kamalakannan Kailasam. "Metal-Free Heptazine-Based Porous Polymeric Network as Highly Efficient Catalyst for CO2 Capture and Conversion". Frontiers in Chemistry 9 (15 de octubre de 2021). http://dx.doi.org/10.3389/fchem.2021.737511.

Texto completo
Resumen
The capture and catalytic conversion of CO2 into value-added chemicals is a promising and sustainable approach to tackle the global warming and energy crisis. The nitrogen-rich porous organic polymers are excellent materials for CO2 capture and separation. Herein, we present a nitrogen-rich heptazine-based microporous polymer for the cycloaddition reaction of CO2 with epoxides in the absence of metals and solvents. HMP-TAPA, being rich in the nitrogen site, showed a high CO2 uptake of 106.7 mg/g with an IAST selectivity of 30.79 toward CO2 over N2. Furthermore, HMP-TAPA showed high chemical and water stability without loss of any structural integrity. Besides CO2 sorption, the catalytic activity of HMP-TAPA was checked for the cycloaddition of CO2 and terminal epoxides, resulting in cyclic carbonate with high conversion (98%). They showed remarkable recyclability up to 5 cycles without loss of activity. Overall, this study represents a rare demonstration of the rational design of POPs (HMP-TAPA) for multiple applications.
Los estilos APA, Harvard, Vancouver, ISO, etc.
49

Sun, Xiao‐Hua, Xue‐Wen Zhang, Fei Wang, Jie Xu y Bing Xue. "Mesostructured Bifunctional ZnBr2/g‐C3N4 Catalysts Towards Efficient Cocatalyst‐Free Cycloaddition of CO2 to Propylene Carbonate". ChemistrySelect 9, n.º 40 (octubre de 2024). http://dx.doi.org/10.1002/slct.202403402.

Texto completo
Resumen
AbstractCatalytic cycloaddition of CO2 with propylene oxide (PO) is a sustainable pathway for the synthesis of propylene carbonate (PC), and the design of efficient heterogeneous catalysts is a hot research topic in both C1 chemistry and functional materials. In this work, graphitic carbon nitride (g‐C3N4) materials were prepared using urea (U) and melamine (M) as precursors through one‐step thermal condensation and then applied as catalyst supports for ZnBr2. As heterogeneous catalysts, the synthesized composites (ZnBr2/g‐C3N4‐MU) exhibited higher activity in the cycloaddition reaction of CO2 to PC than ZnBr2/g‐C3N4‐M and ZnBr2/g‐C3N4‐U. The preparation temperature of ZnBr2/g‐C3N4‐MU could affect the distributions of nitrogen species and acidic strength, which thus determined the final catalytic activity. More importantly, the loading of ZnBr2 not only introduced acidic sites but also enhanced the strength of alkaline sites of g‐C3N4‐MU, enabling ZnBr2/g‐C3N4‐MU materials as acid–base bifunctional catalysts in cycloaddition of CO2 with PO.
Los estilos APA, Harvard, Vancouver, ISO, etc.
50

Liu, Wenxiu, Lei Li, Wei Shao, Hui Wang, Yun Dong, Ming Zuo, Jiandang Liu et al. "Vacancy-Cluster-Mediated Surface Activation for Boosting CO2 Chemical Fixation". Chemical Science, 2022. http://dx.doi.org/10.1039/d2sc05596a.

Texto completo
Resumen
The cycloaddition of CO2 with epoxides towards cyclic carbonates provides a promising pathway for CO2 utilization. Given the crucial role of epoxide ring opening in determining the reaction rate, designing...
Los estilos APA, Harvard, Vancouver, ISO, etc.
Ofrecemos descuentos en todos los planes premium para autores cuyas obras están incluidas en selecciones literarias temáticas. ¡Contáctenos para obtener un código promocional único!

Pasar a la bibliografía