Phosphorylated PEG (PPEG) as a new support for generation of nano‐Pd(0): application to the Heck–Mizoroki and Suzuki–Miyaura coupling reactions

Abstract

Polyethylene glycols (PEGs) with different molecular weights (M w = 200, 400, 1000) were phosphorylated to their bis-diphenyl phosphinite derivatives as stable solids which are melted in the range 140-160 C. These phosphorylated PEGs were used as ligands and reducing agents to generate nano-Pd(0) catalysts in 2.5-8.3 nm. The nano-Pd(0) particles supported on phosphorylated PEG 200 were applied for the efficient Heck-Mizoroki carbon-carbon coupling reactions of ArX (X = Cl, Br, I) at 80-100 C under solvent-free conditions and for the Suzuki-Miyaura coupling reaction in ethanol at 70 C. The catalyst was recycled easily and reused for several runs.

Maghemite decorated with ultra-small palladium nanoparticles (γ-Fe2O3–Pd): applications in the Heck–Mizoroki olefination, Suzuki reaction and allylic oxidation of alkenes

“…Recent examples of such Pd supported catalysts/ nanocatalysts 19 include immobilization of Pd(II) on various solid supports such as phosphorylated polyethylene glycols (PPEG), 20 carbon, 21 polymers, 22 silica, 23,24 zeolites, 25 corn starch 26 and cellulose. 27,28 From a sustainability viewpoint, high catalytic efficiency, selectivity, convenient separation (isolation) and recyclability are viewed as the main desirable attributes for metal nanocatalysts.…”

The Role of PEG on Pd- and Cu-Catalyzed Cross-Coupling Reactions

“…In 2013, Iranpoor and co-workers reported the phosphorylation of PEGs with different molecular weights (MW = 200, 400, 1000) as a simple and practical route for the synthesis of PEG-based phosphinite ligands. 14 They prepared PEG bis-diphenylphosphinite derivatives and used them as ligands and reducing agents to generate nano-Pd(0) catalysts. These nano-Pd(0) particles supported on phosphorylated PEG-200 were applied in efficient Heck-Mizoroki reactions of several haloarenes under solvent-free conditions (Scheme 4).…”

“…45 As already discussed in section 2.2, Iranpoor and coworkers synthesized phosphorylated PEG as a new support for the generation of nano-Pd(0). 14 This system has also been successfully applied to Suzuki-Miyaura coupling reactions.…”

Modification of Montmorillonite with Polyethylene Oxide and Its Use as Support for Pd0 Nanoparticle Catalysts

“…Also, PEO is known as an effective stabilizer for transition metal nanoparticles in reducing of their agglomeration to form big-sized particles [24,25]. PEO itself has been used as a polymer support for Pd catalysts in Heck reactions [26,27,28]. For example, PEO-supported recyclable NC palladacycle catalysts were developed by Karami and co-workers [28] by blending of dimeric NC palladacycle with PEO melts at 85 °C.…”