Preparation and characterization of palladium immobilized on silica‐coated Fe₃O₄ and its catalytic performance for Suzuki reaction under microwave irradiation

Abstract

Supported palladium catalyst (Pd/Fe3O4@SiO2) was easily prepared by supporting PdCl2 on silica‐coated magnetic nanoparticles Fe3O4 in ethylene glycol. The as‐prepared sample was characterized by infrared spectroscopy (IR), X‐ray diffraction (XRD) and X‐ray photoelectron spectrometer (XPS). The formation of active specie Pd(0) was confirmed by XRD and XPS, and the Pd loading for the fresh and recovered catalyst was determined by atomic absorption spectroscopy (AAS). Pd/Fe3O4@SiO2 was employed for the synthesis of biphenyl derivatives via Suzuki reaction. In terms of the yield of biphenyl, the supported catalyst displayed nearly equal catalytic performance to that of homologous PdCl2 under microwave irradiation for 30 min but higher than that obtained by traditional heating method for 12 h. The catalytic performance of Pd/Fe3O4@SiO2 for Suzuki reactions involving various aryl halides and arylboronic acids were also examined. Impressive yield of biphenyl at 68.2% was obtained even in the presence of unreactive aryl chlorides. Pd/Fe3O4@SiO2 was recovered by a permanent magnet and directly reused in the next run, and no obvious deactivation was observed for up to 6 times. Copyright © 2016 John Wiley & Sons, Ltd.

Supramolecular photocatalyst of Palladium (II) Encapsulated within Dendrimer on TiO2 nanoparticles for Photo‐induced Suzuki‐Miyaura and Sonogashira Cross‐Coupling reactions

“…These results proposed that the improved photoactivity predominantly benefits from the synergistic effects of Pd (II) amine‐terminated poly (triazine‐triamine) dendritic on TiO 2 nanoparticles that cause efficient separation and photogenerated electron–hole pairs and photoredox capability of nanocatalyst which all of these advantages due to the tuning of band gap of catalyst in the visible light region. It should be noted that there are many reports of cross‐coupling reactions catalyzed via homogeneous or heterogeneous processes, but most of them need to be conducted at elevated temperatures (≥100 °C), even under reflux conditions . This study shows that visible light irradiation can drive the same reactions on the Pd (II) [PTATAD] @ TiO 2 under much milder reaction conditions (27–30 °C), achieving good to excellent yields, and no additional additives such as co‐catalysts or phosphine ligands are required.…”

“…It should be noted that there are many reports of cross-coupling reactions catalyzed via homogeneous or heterogeneous processes, but most of them need to be conducted at elevated temperatures (≥100°C), even under reflux conditions. [53][54][55][56][57][58][59][60][61][62] This study shows that visible light irradiation can drive the same reactions on the Pd (II) [PTATAD] @ TiO 2 under much milder reaction conditions (27-30°C), achieving good to excellent yields, and no additional additives such as cocatalysts or phosphine ligands are required.…”

Engineered mesoporous ionic‐modified γ‐Fe2O3@hydroxyapatite decorated with palladium nanoparticles and its catalytic properties in water

“…The DABCO structure in the nanocomposite was evident from the characteristic bands at 1462 cm −1 for tertiary amine group and 1213 cm −1 for C&bond;N stretching vibration . Pd NPs do not have any absorption bands in the infrared region and the FT‐IR spectrum of IM‐MHA‐Pd is similar to that of the IM‐MHA nanocomposite …”

Eco-Friendly Physical Activation Methods for Suzuki–Miyaura Reactions

“…An effective methodology has been developed for the coupling of aryl halides (including aryl chloride) and phenylboronic acid under MW irradiation for 30 min in the presence of Pd/Fe 3 O 4 @SiO 2 and K 2 CO 3 [95]. The catalyst was prepared by simply supporting PdCl 2 on Fe 3 O 4 @SiO 2 in ethylene glycol and it was easily recovered using an external magnet after the reaction and reused without further treatment.…”