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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]

A simple and efficient method for the oxidation of primary and secondary alcohols to the corresponding aldehydes and ketones with HO/(NH4)MoO4HO using the PEG-DIL/methylcyclohexane temperature-dependent biphasic system has been developed. The product can be easily isolated by a simple decantation, and the catalytic system can be recycled or reused without loss of catalytic activity. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

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]

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]

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]