Palladium nanoparticles supported on LDH: A highly efficient and recyclable heterogeneous catalyst for the Heck reaction

By using MgAl layered double hydroxide (LDH) as the host material, a novel composite Pd@MgAl-LDH was prepared by assembling the precursor (PdCl42-) with the exfoliated LDH nanosheets followed by in-situ reduction. The heterogeneous catalyst was characterized by various characterization methods. The evenly distributed Pd NPs with an average particle size of about 3.27 nm were successfully supported on LDH nanosheets. The het-erogeneous Pd@MgAl-LDH catalyst exhibited excellent catalytic efficiency for the Heck reaction of iodobenzene and methyl acrylate with the turnover frequency (TOF) value of 4180 h-1 under the optimum conditions. Furthermore, the catalyst offered easy preparation, and good stability toward the Heck coupling reaction and could be reused 5 times without obvious loss of catalytic activity.