Halide-Enhanced Catalytic Activity of Palladium Nanoparticles Comes at the Expense of Catalyst Recovery
AbstractIn this communication, we present studies of the oxidative homocoupling of arylboronic acids catalyzed by immobilised palladium nanoparticles in aqueous solution. This reaction is of significant interest because it shares a key transmetallation step with the well-known Suzuki-Miyaura cross-coupling reaction. Additives can have significant effects on catalysis, both in terms of reaction mechanism and recovery of catalytic species, and our aim was to study the effect of added halides on catalytic efficiency and catalyst recovery. Using kinetic studies, we have shown that added halides (added as NaCl and NaBr) can increase the catalytic activity of the palladium nanoparticles more than 10-fold, allowing reactions to be completed in less than half a day at 30 °C. However, this increased activity comes at the expense of catalyst recovery. The results are in agreement with a reaction mechanism in which, under conditions involving high concentrations of chloride or bromide, palladium leaching plays an important role. Considering the evidence for analogous reactions occurring on the surface of palladium nanoparticles under different reaction conditions, we conclude that additives can exert a significant effect on the mechanism of reactions catalyzed by nanoparticles, including switching from a surface reaction to a solution reaction. The possibility of this switch in mechanism may also be the cause for the disagreement on this topic in the literature. View Full-Text
Share & Cite This Article
Bouleghlimat, A.; Othman, M.A.; Lagrave, L.V.; Matsuzawa, S.; Nakamura, Y.; Fujii, S.; Buurma, N.J. Halide-Enhanced Catalytic Activity of Palladium Nanoparticles Comes at the Expense of Catalyst Recovery. Catalysts 2017, 7, 280.
Bouleghlimat A, Othman MA, Lagrave LV, Matsuzawa S, Nakamura Y, Fujii S, Buurma NJ. Halide-Enhanced Catalytic Activity of Palladium Nanoparticles Comes at the Expense of Catalyst Recovery. Catalysts. 2017; 7(9):280.Chicago/Turabian Style
Bouleghlimat, Azzedine; Othman, Mazin A.; Lagrave, Louis V.; Matsuzawa, Soichiro; Nakamura, Yoshinobu; Fujii, Syuji; Buurma, Niklaas J. 2017. "Halide-Enhanced Catalytic Activity of Palladium Nanoparticles Comes at the Expense of Catalyst Recovery." Catalysts 7, no. 9: 280.
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.