Fe₃O₄‐SAHPG‐Pd⁰ nanoparticles: A ligand‐free and low Pd loading quasiheterogeneous catalyst active for mild Suzuki–Miyaura coupling and CH activation of pyrimidine cores

Abstract

This paper reports a green magnetic quasiheterogeneous efficient palladium catalyst in which Pd 0 nanoparticles have been immobilized in self-assembled hyperbranched polyglycidole (SAHPG)-coated magnetic Fe 3 O 4 nanoparticles (Fe 3 O 4-SAHPG-Pd 0). This catalyst has been used for effective ligandless Pd catalyzed Suzuki-Miyaura coupling reactions of different aryl halides with substituted boronic acids at room temperature and in aqueous media. Herein, SAHPG is used as support; it also acts as a reducing agent and stabilizer to promote the transformation of Pd II to Pd 0 nanoparticles. Also, this environmental friendly quasiheterogeneous catalyst is employed for the first time in the synthesis of new pyrimido[4,5-b]indoles via oxidative addition/C H activation reactions on the pyrimidine rings, which were obtained with higher yield and faster than when Pd(OAc) 2 was used as the catalyst. Interestingly, the abovementioned catalyst could be recovered in a facile manner from the reaction mixture by applying an external magnet device and recycled several times with no significant decrease in the catalytic activity.

Palladium nanoparticles for the synthesis of phenanthridinones and benzo[c]chromenes via C–H activation reaction

“…50 For instance, Pd NPs were recently explored in C-H bond activation reactions for heterocyclic compounds functionalization, [51][52][53][54][55][56][57][58][59][60][61] or heterocycles synthesis via cyclization reactions. [62][63][64][65] The synthesis of phenanthridine-6(5H)-ones and benzo[c] chromenes by direct arylation reaction catalyzed by Pd NPs was recently reported. Saka et al described the synthesis of phenanthridine-6(5H)-ones employing binaphthyl-supported Pd NPs (Pd-BNP) in a multiple C-H activation reaction (by consecutive C-C and C-N bond formations) with N-methoxybenzamides and aryl iodides (path iv; Fig.…”

“…50 For instance, Pd NPs were recently explored in C–H bond activation reactions for heterocyclic compounds functionalization, 51–61 or heterocycles synthesis via cyclization reactions. 62–65…”

Designing a new method for growing metal–organic framework (MOF) on MOF: synthesis, characterization and catalytic applications

“…Within this context and with the consideration of all the aforementioned points, and also in the continuation of our investigation towards the development of efficient heterogeneous catalysts, [49][50][51][52][53][54][55][56][57][58] herein, we endeavored to design and prepare a dual magnetic MOF nanostructured catalyst (Fe 3 O 4 -MAA@Co-MOF@Cu-MOF NPs) for the synthesis of 4(3H)-quinazolinone derivatives. 4(3H)-quinazolinones as an important class of nitrogen-containing heterocyclic compounds 59,60 have attracted much attention due to their pharmacological and biological applications, including antibacterial, anti-infective, anti-inflammatory, anti-ulcer, anticonvulsant, hypolipidemic, anticancer, and antitumor properties.…”

Fe3O4@CS‐Ni: An efficient and recyclable magnetic nanocatalyst for α‐alkylation of ketones with benzyl alcohols by borrowing hydrogen methodology

“…[25] A promising alternative is heterogeneous supports due to their simple separation from the reaction mixture and reutilization. [26] In this regard, a broad range of catalyst supports such as active carbon, [27] zeolites, [28] alumina, [29] silica, [30,31] metal oxides, [32] graphene oxide, [33][34][35] polymers, [36] and carbon nanofibers [37] have so far been explored to produce heterogeneous catalytic systems. Among the mentioned supports, carbohydrates occupied a privileged position due to their ability to stabilize nanoparticles.…”