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A new catalyst based on palladium nanoparticles immobilized on nano‐silica triazine dendritic polymer (Pdnp‐nSTDP) was synthesized and characterized by FT‐IR spectroscopy, thermogravimetric analysis, field emission scanning electron microscopy, energy dispersive X‐ray, transmission electron microscopy and elemental analysis. The size of the palladium nanoparticles was determined to be 3.1±0.5 nm. This catalytic system showed high activity in the Suzuki–Miyaura cross‐coupling of aryl iodides, bromides and chlorides with arylboronic acids and also in the Heck reaction of these aryl halides with styrenes. These reactions were best performed in a dimethylformamide (DMF)/water mixture (1:3) in the presence of only 0.006 mol% and 0.01 mol% of the catalyst, respectively, under conventional conditions and microwave irradiation to afford the desired coupling products in high yields. The Pdnp‐nSTDP was also used as an efficient catalyst for the preparation of a series of star‐ and banana‐shaped compounds with a benzene, pyridine, pyrimidine or 1,3,5‐triazine unit as the central core. Moreover, the catalyst could be recovered easily and reused several times without any considerable loss of its catalytic activity.

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A novel heterogeneous catalyst was synthesized by immobilization of a carboxylic acid-and imidazolium-based ionic liquid on the mesoporous MIL− 101(Cr) (MIL−101(Cr)−TSIL) and used to convert abundant, nontoxic, economical and renewable CO 2 gas to cyclic carbonates without the need for a cocatalyst or a solvent. The catalyst was characterized in detail by multiple techniques such as XRD, TEM, SEM, EDX, DR-FTIR, solid-state NMR, as well as N 2 and CO 2 adsorption measurements. The catalytic properties were studied by varying different parameters including amount of catalyst and epoxide, temperature, pressure, and reaction time. Under optimal conditions (100 mg catalyst, 15 mmol epoxide, 2.0 MPa CO 2 pressure, 110 °C and 2 h reaction time) various cyclic carbonates were obtained with high yield and selectivity. MIL−101(Cr)−TSIL catalyst displayed good thermal stability and could be reused after simple separation without a significant decrease in its catalytic activity. Due to synergetic effect of the hydrogen bond from the carboxylic acid group for activation of the C−O bond of the epoxide, adsorption of CO 2 by the imidazolium moiety, and high concentration of CO 2 around the task specific ionic liquid (TSIL), arisen from the mesoporous framework, MIL−101(Cr)−TSIL is a highly effective catalytic system for the solvent-free cycloaddition of CO 2 with epoxide.

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An efficient, atom-economical, and regioselective synthesis of a wide range of 1,4-disubstituted 1,2,3-triazoles in excellent yields has been achieved via a one-pot three-component reaction of alkynes and sodium azide with organic halides or α-bromo ketones catalyzed by Cu(II)-TD@nSiO2/sodium ascorbate at room temperature. This catalytic system also showed excellent activity in the synthesis of bis- and tris-1,4-substituted 1,2,3-triazoles. Moreover, the catalyst could be recycled and reused for seven cycles without any loss in its catalytic activity.