Assemblies of Copper Ferrite and Palladium Nanoparticles on Silica Microparticles as a Magnetically Recoverable Catalyst for Sonogashira Reaction under Mild Conditions

Abstract

Copper ferrite and palladium nanoparticles assembled on silica microparticles are prepared successfully and characterized by scanning electron microscopy, transmission electron microscopy, electron‐dispersive X‐ray analysis, X‐ray diffraction, thermogravimetric analysis, atomic absorption spectroscopy, and infrared studies. The catalyst is applied effectively for the Sonogashira coupling reaction of aryl iodides and bromides under heterogeneous and phosphine‐free reaction conditions. The reactions proceed at 50 °C with a low loading of palladium catalyst. The magnetically recoverable catalyst is recycled successfully for five consecutive runs with very small drops in catalytic activity.

Suzuki–Miyaura coupling catalyzed by palladium nanoparticles biosynthesized using Glycyrrhiza glabra as reducing and stabilyzing agent

“…Further, the XRD pattern was compared with JCPDS standard (no. 05–0681) and confirmed the formation of Pd‐NPs with cubic (face‐centred cubic) crystal structure, which is also consistent with earlier reports …”

Effect of addition of iron on morphology and catalytic activity of PdCu nanoalloy thin film as catalyst in Sonogashira coupling reaction

“…Kohler and co‐workers reported that the Pd/C‐catalysed Sonogashira reaction of iodobenzene with phenylacetylene without the addition of CuI or PPh 3 gives TOF = 1184 h −1 and TON =592 . Gholinejad and Ahmadi reported that the Sonogashira reaction over Pd–CuFe 2 O 4 /SiO 2 catalyst gives TOF = 10.97 h −1 . Under similar conditions, Basu and co‐workers, Metin and co‐workers and Gao and co‐workers reported the Sonogashira reaction with Pd/Cu‐ARF(II) (TOF = 43.43 h −1 ), Cu 48 Pd 52 /RGO (TOF = 145.26 h −1 ) and MMT/Pd‐Cu (TOF = 6.06 h −1 ) catalysts, respectively.…”

Solid-Supported Palladium Catalysts in Sonogashira Reactions: Recent Developments

“…This spinel was linked to a silica surface through an aminopropylsilaneoxy linker, and over this material PdNPs were deposited to obtain material 66. The catalyzed Sonogashira reaction was carried out using different functionalized iodo-and bromoarenes [112], the presence of electron-withdrawing groups at the p-position of the haloarene enhancing the chemical yield. It should be pointed out that the magnetic decantation of the catalyst and its reuse had a negative impact on the final yield, as it was explained by the high palladium leaching (6%), according to AAS analysis of the crude solution.…”