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    Monodisperse palladium nanoparticles supported on chemically derived graphene: highly active and reusable nanocatalysts for Suzuki-Miyaura cross-coupling reactions
    (Tubitak Scientific & Technological Research Council Turkey, 2015) Durap, Feyyaz; Metin, Onder
    Addressed herein is the catalysis of monodisperse palladium nanoparticles (NPs) supported on chemically derived graphene (CDG) for the Suzuki-Miyaura cross-coupling of phenylboronic acid and various aryl halides. Monodisperse Pd NPs were synthesized by the solution phase reduction of palladium(II) acetylacetonate with morpholine borane complex in oleylamine and deposited on CDG via the liquid phase self-assembly method. Colloidal Pd NPs and CDG-Pd catalyst were characterized by TEM, XRD, SEM, and ICP-MS analyses. The CDG-Pd catalyst showed high activity in the Suzuki-Miyaura cross-couplings of different aryl halides including iodides, bromides, and even chlorides with phenylboronic acid under mild conditions. More importantly, the reusability experiments revealed that CDG-Pd catalyst was highly durable by almost maintaining its inherent activity after the 15th catalytic cycle.
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    Palladium(0) nanoclusters stabilized by poly(4-styrenesulfonic acid-co-maleic acid) as an effective catalyst for Suzuki-Miyaura cross-coupling reactions in water
    (Elsevier, 2011) Metin, Onder; Durap, Feyyaz; Aydemir, Murat; Ozkar, Saim
    Palladium(0) nanoclusters stabilized by poly(4-styrenesulfonic acid-co-maleic acid), PSSA-co-MA, were generated in situ during the hydrolysis of ammonia-borane (AB) from the reduction of potassium tetrachloropalladate(II) in aqueous solution at room temperature. They were isolated from the reaction solution and characterized by UV-visible electronic absorption spectroscopy, TEM, SAED and XRD techniques. The PSSA-co-MA stabilized palladium(0) nanoclusters were used as catalyst in Suzuki-Miyaura cross-coupling reactions of various of arylbromides or aryl iodide with phenylboronic acid in water without any purification process after catalytic hydrolysis of AB. They show excellent catalytic activity in coupling of series of aryl bromides or aryl iodide with phenylboronic acid under the optimized reaction conditions in water. PSSA-co-MA stabilized palladium(0) nanoclusters provided turnover frequency of 1980 and 5940h(-1) in Suzuki-Miyaura coupling reactions of phenylboronic acid with p-bromoacetophenone or p-iodobenzene, respectively, which are the highest values ever reported for the Suzuki-Miyaura coupling reactions in water as sole solvent. (C) 2011 Elsevier B.V. All rights reserved.