Novel palladium nanoparticles supported on β‐cyclodextrin@graphene oxide as magnetically recyclable catalyst for Suzuki–Miyaura cross‐coupling reaction with two different approaches in bio‐based solvents

Abstract

A novel nanocatalyst was designed and prepared. Initially, the surface of magnetic graphene oxide (M-GO) was modified using thionyl chloride, tris(hydroxymethyl)aminomethane and acryloyl chloride as linkers which provide reactive C═C bonds for the polymerization of vinylic monomers. Separately, β-cyclodextrin (β-CD) was treated with acryloyl chloride to provide a modified β-CD. Then, in the presence methylenebisacrylamide as a crosslinker, monomers of modified β-CD and acrylamide were polymerized on the surface of the pre-prepared M-GO. Finally, palladium acetate and sodium borohydride were added to this composite to afford supported palladium nanoparticles. This fabricated nanocomposite was fully characterized using various techniques. The efficiency of this easily separable and reusable heterogeneous catalyst was successfully examined in Suzuki-Miyaura cross-coupling reactions of aryl halides and boronic acid as well as in modified Suzuki-Miyaura crosscoupling reactions of N-acylsuccinimides and boronic acid in green media. The results showed that the nanocatalyst was efficient in coupling reactions for direct formation of the corresponding biphenyl as well as benzophenone derivatives in green media based on bio-based solvents. In addition, the nanocatalyst was easily separable, using an external magnet, and could be reused several times without significant loss of activity under the optimum reaction conditions.

Supramolecular Catalysts for Organic Synthesis: Preparation and Applications of Cyclodextrins and Calixarenes in C−C Cross‐Coupling Reactions

“…Later, in 2018, Heravi, Sedghi and co-workers reported the development of a magnetically recoverable version of this system by supporting Pd NPs over the surface of β-CDfunctionalized magnetic graphene oxide. [47] This novel composite showed promising activity not only in the conventional aqueous Suzuki-Miyaura reaction between aryl halides and boronic acids, but also in the cross-coupling of N-acylsuccinimides and phenylboronic acid in deep-eutectic solvents (DES).…”

Magnetic Nanoparticle Composites: Synergistic Effects and Applications

“…They prepared M-GO/(AM-MBA-𝛽-CD@Pd)(M-GO, magnetic GO; AM, acrylamine; MBA, methylenebisacrylamide) nanocomposites and they used them as recyclable catalysts for Suzuki-Miyaura cross-coupling reactions of aryl halides with boronic acids as well as for modified S-M cross-coupling reactions of Nacylsuccinimides and boronic acid in green media. [330] Another work presents the synthesis of Pd@salen-porphyrin conjugated microporous polymer (Pd@SP-CMP) composites. The functional CMP was used as a Pd NP support due to the coordinate interactions between the polydentate chelating sites with Pd(OAc) 2 and subsequent reduction with NaBH 4 .…”

Deep eutectic solvents: cutting-edge applications in cross-coupling reactions

“…Recently, Heravi, Sedghi, and co-workers identified a new modification of Suzuki-Miyaura cross-coupling reaction using boronic acid as well as N-acylsuccinimides as versatile acyl-transfer reagent instead of aryl halides in ChCl:gly (1:2). 127 The 0.03 mol% of this novel Pd NPs supported on -CD@graphene oxide, as a magnetically reusable heterogeneous catalyst, in the presence of K 2 CO 3 as a base at 90 o C led to the formation of benzophenone derivatives in 5 h with the conversion of 60-89% (Scheme 5). The authors surveyed the effect of several solvents, for example water, ethanol, CH 3 CN and THF accompanied by three types of DESs (ChCl:urea/EG/gly) for finding the best medium.…”