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In this work, a class of transition metal-modified MCM-41 mesoporous silica supported ionic liquids nanocatalysts were constructed and efficiently used as catalysts for the effective carboxylation of terminal alkynes through CO2 utilization. The main factors affecting the catalytic performance of carboxylation and its possible reaction mechanism were sufficiently discussed. The results showed that when the dosage was 0.2 g, the temperature was 40°C and the CO2 pressure was 0.3 MPa, the supported catalyst MCM-41@IL-Sm showed the optimal catalytic efficiency. The novel catalyst proved to be highly efficient for the sustainable synthesis of alkynyl carboxylic acids attributing good to excellent yields of 82%–95% within 7–12 h. Moreover, MCM-41@IL-Sm could be recycled and reused six times without noticeable decrease in catalytic activity from two-phase system under external heterogeneous field. The application of supported ionic liquids in the field of carbon dioxide carboxylation has injected a new power source for the efficient and effective production of value-added chemicals from waste CO2. [ABSTRACT FROM AUTHOR]

In this study, we report a successful strategy for the generation of a type of multifunctional heterogeneous supported ionic liquids catalysts. The synthesized supported ionic liquids (Fe‐MCM‐41/IL) were used in the catalytic cyclocondensation of 2‐aminobenzamide and various ketones and aldehydes towards the efficient synthesis of the dihydroquinazolinones under green conditions. The influence of the different catalysts and reaction parameters on the catalytic behaviors were sufficiently investigated. The supported catalyst (2)Fe‐MCM‐41/IL(0.6) showed the optimal catalytic efficiency. A hot filtration experiment revealed that the reaction proceeded in a heterogeneous pathway. The catalytic activity of (2)Fe‐MCM‐41/IL(0.6) could be maintained efficiently after recycling up to five consecutive runs under the optimized reaction conditions. Merits of this meticulously designed protocol are the use of novel supported catalyst, easy work‐up process, feasibility and sustainability, indicating its potential industrial application prospect. [ABSTRACT FROM AUTHOR]

A type of MCM-41 supported dual imidazolium ionic liquids have been synthesized and efficiently used as catalysts in the sustainable chemical conversion of CO2 and epoxides into cyclic carbonates. It was shown that the highest efficiency was achieved in the cycloaddition of a variety of epoxides and CO2 in the presence of the MCM-41@DILSCN solid catalyst under mild conditions. More interestingly, the catalyst was stable, very active, robust, and displayed good recyclability without significant loss of catalytic activity after six consecutive cycles during the process. Overall, the present protocol of synthesizing cyclic carbonates under solvent free conditions using MCM-41@DILSCN is promising for industrial applications. [ABSTRACT FROM AUTHOR]

Global warming and climate change concerns are triggering worldwide interest for sustainable transformation of CO2 into useful chemicals. Here, a new and efficient multifunctional catalytic system for the cycloaddition of carbon dioxide with epoxides to synthesize cyclic carbonates under mild and solvent-free reaction conditions has been developed. The catalytic tests revealed that [P12,4,4,4]Br/MIL-53(Cr) (MIL: Materials of Institut Lavoisier) was the best and powerful catalytic system in the cycloaddition with excellent yields (96-99%) under solvent-free condition and 100 °C, 1.0 MPa for 2-3 h. The synergistic effect of anion and cation of ionic liquid [P12,4,4,4]Br as well as the chromium site of cocatalyst MIL-53(Cr) contributed to the excellent catalytic activity. The present catalytic system has several unique features such as simple operation, good to excellent yields, high catalytic activity, environmentally benign and safe. This study provides a sustainable and efficient synergistic strategy for chemical carbon dioxide fixation via the combination of ionic liquids and metal-organic frameworks. [ABSTRACT FROM AUTHOR]

A series of functionalized ionic liquids immobilized onto SBA‐15 mesoporous materials were prepared, characterized and evaluated as catalysts in cycloaddition of CO2 to epoxides. Most of these immobilized ILs perform well in the reaction, especially the multifunctional titanium incorporated SBA‐15 immobilized heterogeneous catalysts Ti‐SBA‐15@ILClCH2COO(0.5) and Al‐SBA‐15@ILClCH2COO(0.5). The catalytic tests revealed that Ti‐SBA‐15@ILClCH2COO(0.5) was the best and powerful catalyst in the cycloaddition for the preparation of cyclic carbonates with high to excellent yields. The heterogeneous catalyst can be easily separated from the reaction mixture by filtration and reused in six consecutive cycles without significant loss in catalytic activity. The studies demonstrate that the well designed supported catalysts via cooperative catalysis of the supported carrier, anion sites of ILs is a promising platform for construction of novel and highly efficient catalytic transformation systems. [ABSTRACT FROM AUTHOR]

Abstract: A supported ionic liquid ILCF3SO3@SiO2 was synthesized and used as a highly efficient catalyst in the Paal-Knorr reaction for the preparation of pyrroles. The heterogeneous catalyst could be easily recovered and recycled for five times without noticeable loss of catalytic activity. Also a possible reaction mechanism is provided.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Nano‐silica supported ionic liquids composed of alkyl carbon chain and transition metal chlorides anions have been prepared and successfully applied as a heterogeneous catalyst in the direct aldehyde C‐H activation. Catalytic results indicated that nano‐SiO2 supported ionic liquid consisting C12 alkyl carbon chain and CoCl3 anion nano‐SiO2@CoCl3‐C12IL showed excellent catalytic properties with good to excellent yields towards the desired aryl ketones. The excellent recyclability of the supported catalyst, mild reaction conditions, low catalyst loading, and operational simplicity are the important features of this methodology. [ABSTRACT FROM AUTHOR]

A general and efficient catalytic system for Pd 2 (dba) 3 -catalyzed ligand-free Suzuki cross-coupling reactions was developed. The cross-couplings of a wide range of aryl halides with various arylboronic acids were feasible under mild conditions in environmental friendly [hmim]NTf 2 /supercritical CO 2 biphasic system employing K 2 CO 3 as a base, which provided in good to high yields to the corresponding products. The catalytic system could be recycled and reused without significant loss of catalytic activity. Additionally, a possible mechanism of the Suzuki cross-coupling reaction is depicted in this paper. [ABSTRACT FROM AUTHOR]

In this work, a functionalizing active species 4-methylbenzenesulfonic acid-based IL on silica gel (IL-SOH-SiO) has been prepared, and characterized by FT-IR, XRD, TGA, SEM and EDX spectra. Then, IL-SOH-SiO was utilized as an efficient and heterogeneous catalyst for the synthesis of indoles via the one-pot Fischer reaction of phenyl hydrazines with ketones or aldehydes at room temperature. The heterogeneous catalyst could be recovered easily by filtration and reused many times without significant loss of its catalytic activity. Graphical Abstract: [ABSTRACT FROM AUTHOR]

A simple, efficient, and ecofriendly procedure for the aerobic oxidation of alcohols to aldehydes and ketones in the presence of In(NO 3 ) 3 /[C 12 mim][FeBr 4 ] in aqueous media has been developed. The oxidation reactions afford the target products in good to high yields and no over-oxidation was observed. The products can be separated by a simple extraction with dichloromethane, and the system can be recycled and reused without loss of activity. [ABSTRACT FROM AUTHOR]

A facile and efficient synthesis of bibenzyl and biaryl derivatives by reductive homocoupling reaction is described. Treatment of benzyl and aryl halides with metallic zinc and copper powder in the presence of a catalytic amount of [Cmim][CuCl] under ligand- and base-free conditions gives the corresponding bibenzyls and biaryls in good to high yields. The product can be isolated by a simple extraction with organic solvent, and the catalytic system can be recycled or reused without any significant loss of catalytic activity. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: A simple, mild, and efficient procedure for the oxidation of organic halides to aldehydes and ketones with H5IO6 in ionic liquid [C12mim][FeCl4] has been developed. The oxidation reactions afford the target products in good to high yields and no overoxidation was observed. The products can be separated by a simple extraction with organic solvent, and the catalytic system can be recycled and reused without loss of catalytic activity. [Copyright &y& Elsevier]

An immobilized benzotriazolium ionic liquid system has been developed for the efficient catalytic transformation of CO2 to cyclic carbonates without using any co‐catalyst or solvent. Two novel multifunctional periodic mesoporous organosilica supported benzotriazolium ionic liquids PMO‐ILTiCl5 and PMO‐ILSnCl5 were prepared, characterized and demonstrated excellent catalytic activity in the cycloaddition of CO2 with epoxides. The superior catalytic performance was observed for PMO‐ILTiCl5 in the synthesis of cyclic carbonates with high yields and selectivities. Furthermore, the catalyst PMO‐ILTiCl5 could be separated readily and reuse for at least five successful times without obvious losses in its catalytic activity, owing to the presence of intramolecular synergistic effect between active hydroxyl sites and TiCl5 nucleophile and thus provide sufficiently stable catalytic sites. Therefore, this work provided a novel strategy for highly efficient and environmentally benign catalytic conversion of CO2 to cyclic carbonates. [ABSTRACT FROM AUTHOR]

An ionic liquid is used as a catalyst for the synthesis of cyclic carbonates (III) from epoxides (I) and carbon dioxide. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Efficient and Convenient Oxidation of Sulfides to Sulfoxides with Molecular Oxygen Catalyzed by Mn(OAc)2 in Ionic Liquid [C12mim][NO3]" by D. Fang and others, published in the "Royal Society of Chemistry Advances" in 2014.

Periodic mesoporous organosilica (PMO) supported ionic liquids with high catalytic ability were prepared and tested in synthesis of 2‐oxazolidinones from the three‐component cycloaddition reactions of CO2, aryl amines and epoxide. The functionalized PMO material PMO@TZ‐ILSmCl4 revealed the most excellent catalytic performance than PMO@TZ‐ILLaCl4 during the catalytic synthesis of 2‐oxazolidinones. Different parameters such as catalyst loading, temperature, CO2 pressure and reaction time were also investigated. Good to excellent yields for 2‐oxazolidinones and stable reusability were reached in the CO2 cycloaddition under solvent‐ /ligand‐free conditions. This work provides a useful route to design novel and highly efficient catalytic systems for the transformation of CO2 into other valuable 2‐oxazolidinones. [ABSTRACT FROM AUTHOR]

The Heck reaction of aryl halides with terminal olefins was successfully performed by using Pd (OAc)2 as the catalyst in a ligand-free PEG1000-DIL (PEG1000-based dicationic ionic liquid)/toluene system exhibiting temperature-dependent biphasic behavior. In addition, the isolation of the products is readily performed by a simply decantation, and the catalytic system can be recycled and reused without loss of catalytic activity. [ABSTRACT FROM AUTHOR]

Mesoporous material supported functionalized ionic liquids have been designed and synthesized, characterized and evaluated as novel heterogeneous catalysts for the Hantzsch reaction. The as‐fabricated catalysts show good performance in the Hantzsch synthesis of 1,4‐dihydropyridines under ambient conditions, especially the titanium incorporated mesoporous material supported ionic liquid Ti‐SBA‐15@IL‐BF4, based on a synergetic effect of titanium site of mesoporous material carrier and the acidic sites of ionic liquid. In addition, the heterogeneous catalyst offers simple operation for recovery and the recycling test showed that it could be reused for five times without significant loss of catalytic activity. Mesoporous material supported functionalized ionic liquids have been designed and synthesized, and evaluated as heterogeneous catalysts for the Hantzsch reaction. Research shows that Ti‐SBA‐15@IL‐BF4 show the best catalytic performance under ambient conditions. The catalyst offers simple operation for recovery and the recycling test showed that it could be reused for five runs without significant loss of catalytic activity, thus making this method economical and environment‐friendly. [ABSTRACT FROM AUTHOR]

Novel periodic mesoporous organosilica supported nanocatalysts with different loading levels of a bis(trifluoromethylsulfonyl)imide anion-based dual imidazolium ionic liquid have been prepared and evaluated as efficient catalysts for the cycloaddition of CO2 to epoxides. The as-fabricated PMO@IL-NTf2(1.0) exhibited the best catalytic performance with excellent conversions (98–100%) and yields (96–99%) at 90 °C and 0.6 MPa for 0.5–1 h, based on a synergistic effect between the dual nucleophilic anion sites of the imidazolium ionic liquid and the hydroxyl group sites of periodic mesoporous organosilica. The excellent recyclability and operational simplicity make this protocol economic and environment-friendly. [ABSTRACT FROM AUTHOR]

A series of MCM-41 supported functionalized ionic liquids doped with copper species were prepared, characterized and evaluated as catalysts in the Biginelli reaction. Most of these supported ionic liquids perform well in the reaction, especially the multifunctional copper coordinated MCM-41 supported heterogeneous catalysts (0.5)IL-TiCl 5 @MCM-41@Cu(15) and (0.5)IL-HSO 4 @MCM-41@Cu(15). The catalytic tests revealed that (0.5)IL-HSO 4 @MCM-41@Cu(15) was the best and powerful catalyst in the Biginelli reaction for the preparation of 3,4-dihydropyrimidinones with high to excellent yields. The catalyst can be easily separated from the reaction mixture by filtration and reused in six consecutive cycles without significant loss in catalytic activity. [ABSTRACT FROM AUTHOR]

Novel mesoporous silica supported ILs have been prepared and successfully applied as a heterogeneous catalyst in Mannich reactions. The excellent recyclability of the supported catalyst, mild reaction conditions, good to excellent yields, low catalyst loading, and operational simplicity are the important features of this methodology. [ABSTRACT FROM AUTHOR]