Synthesis and characterization of mesoporous organosilica supported palladium (SBA‐Pr‐NCQ‐Pd) as an efficient nanocatalyst in the Mizoroki–Heck coupling reaction

Abstract

In the present study, the modification of a mesoporous organosilica nanocomposite SBA‐15 (Santa Barbara Amorphous 15) was carried out in two steps, first through the surface functionalization of SBA‐Pr‐NH2 with 2‐chloroquinoline‐3‐carbaldehyde to form SBA‐Pr‐NCQ, and then through a post‐modification process with palladium ions. The target nanocompound structure of SBA‐Pr‐NCQ‐Pd was characterized by different techniques (thermogravimetric analysis, X‐ray diffraction, scanning electron microscopy, Energy‐dispersive X‐ray spectroscopy (EDX), and Fourier transform infrared spectroscopy). The catalytic performance of the porous inorganic–organic hybrid nanocomposite (SBA‐Pr‐NCQ‐Pd) in one of the most important carbon–carbon bond‐forming processes, the Mizoroki–Heck coupling reaction of aryl halides and methacrylate in water/ethanol media, was examined. Compared to previous reports, this protocol afforded some advantages, such as high yields of products, short reaction times, catalyst stability without leaching, simple methodology, easy workup, and greener conditions. Also, the nanocatalyst can be easily separated from the reaction mixture and reused several times without a significant decrease in activity and promises economic as well as environmental benefits.

Visible Light Mediated Heck Coupling of Inactivated Aryl Fluoride/Chloride Over a Sulfonic Acid Functionalized, Melamine‐based Metal‐free Porphyrin Photocatalyst

“…[30] With the perception to develop heterogeneous process, mesoporous silica comprising palladium nanoparticles have been synthesized and successfully used for sustainable CÀ C coupling reactions. [31][32][33] Besides, novel heterogeneous catalysts were obtained by incorporating Pd-nano particles supported on carbon nitride have appeared as the robust candidates against leaching, accumulation with excellent workability for aqueous-based CÀ C couplings. [34,35] Similarly, Maryam and his group scrutinized Pd-nanoparticles supported on reduced graphene oxide, for effective coupling of various aryl iodides with different alkenes in the presence of…”

“…Another group designed Pd based catalyst on DABCO modified silica support demonstrating good stability and high activity in the Mizoroki‐Heck cross‐coupling involving different aryl halides and alkenes [30] . With the perception to develop heterogeneous process, mesoporous silica comprising palladium nanoparticles have been synthesized and successfully used for sustainable C−C coupling reactions [31–33] . Besides, novel heterogeneous catalysts were obtained by incorporating Pd‐nano particles supported on carbon nitride have appeared as the robust candidates against leaching, accumulation with excellent workability for aqueous‐based C−C couplings [34,35] .…”

Porous carbon supported Pd catalysts derived from gelatin‐based/chitosan or polyvinyl pyrrolidone/PdCl2 blends

“…Heterogeneous catalysis can effectively resolve these problems. Various well-defined nanostructured solid matrices, including biopolymers, 7,20-23 carbon materials, 24,25 clay, 26,27 and silica 28 and so on, have been employed to support Pd catalysts for the accomplishment of green and economical Heck coupling reactions.…”

Immobilizing palladium on melamine‐functionalized magnetic nanoparticles: An efficient and reusable phosphine‐free catalyst for Mizoroki–Heck reaction

“…Moreover, as a means to combine the advantages of homogeneous and heterogeneous catalytic processes, nanoparticles have been widely employed recently due to their high surface area and facile recovery. Among them, palladium nanoparticles (Pd NPs) supported on heterogeneous nanoparticles, such as mesoporous organosilica (especially SBA‐15), [ 30 ] boehmite, [ 31,32 ] and hercynite, [ 33 ] are the most relevant type of catalytic systems due to their high reactivity and selectivity in coupling reactions.…”