Palladium Nanoparticles Immobilized on Nano‐Silica Triazine Dendritic Polymer (Pd_np‐nSTDP): An Efficient and Reusable Catalyst for Suzuki–Miyaura Cross‐Coupling and Heck Reactions

Abstract

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.

Eco-Friendly Physical Activation Methods for Suzuki–Miyaura Reactions

“…Isfahani et al [103] have described, for the first time, the synthesis of a new catalyst which is based on Pd nanoparticle immobilized on a nano-silica triazine dendritic polymer (Pdnp-nSTDP) and its subsequent application in C-C coupling reactions. This catalytic system showed high activity in the SMC of aryl iodides, bromides and chlorides with arylboronic acids.…”

Preparation of Pd-Diimine@SBA-15 and Its Catalytic Performance for the Suzuki Coupling Reaction

“…In a 100 mL three-necked round-bottomed flask, 3-aminopropyl trimethoxysilane (APTMS) (8 mL, 45 mmol) was added dropwise to a suspension of SBA-15 (5 g) in dry toluene (30 mL) under a N 2 atmosphere. This mixture solution was refluxed for 24 h. After that, the solid was filtered and washed repeatedly with dichloromethane to remove the unreacted starting material, and dried in a vacuum oven at 120 • C for 8 h. The white powder obtained was designated as APTMS@SBA-15 [45].…”

Magnetic polymer nanocomposite-supported Pd: an efficient and reusable catalyst for the Heck and Suzuki reactions in water

“…The catalyst also exhibited high activity toward various aryl bromides (entries [9][10][11][12][13][14][15][16][17][18][19]. Excellent yields were obtained for aryl bromides bearing electron-withdrawing substituents (entries [10][11][12][13][14].…”

“…In this regard, Isfahani and colleagues 12 recently prepared a new catalyst by immobilizing palladium nanoparticles on the nanosilica triazine dendritic polymer. This catalyst exhibits high activity for the Suzuki and Heck reactions at low concentrations (0.006 mol% and 0.01 mol% palladium respectively for these two reactions).…”