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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]

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 range of multifunctional magnetic metal–organic framework nanomaterials consisting of various mass ratios of the metal–organic framework MIL-53(Fe) and magnetic SiO2 @NiFe2 O4 nanoparticles were designed, prepared, characterized, and evaluated as heterogeneous catalysts for the Knoevenagel condensation. The as-fabricated nanomaterials, especially the nanocatalyst MIL-53(Fe)@SiO2 @NiFe2 O4 (1.0), showed good catalytic performance in the Knoevenagel condensation at room temperature as a result of synergistic interaction between the Lewis acid iron sites of MIL-53(Fe) and the active sites of the magnetic SiO2 @NiFe2 O4 nanoparticles. In addition, the heterogeneous catalyst was readily recovered and a recycling test showed that it could be reused for five times without significant loss of its catalytic activity, making it economical and environmentally friendly. [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]

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]