Efficient Suzuki–Miyaura coupling reaction in water: Stabilized Pdo-Montmorillonite clay composites catalyzed reaction

Abstract

The Pdo-nanoparticles, generated into the nanopores of modified Montmorillonite clay, were evaluated for catalytic performance for the Suzuki–Miyaura cross coupling reactions. The modification of Montmorillonite clay was carried out by activating with H2SO4 under controlled conditions for generating nanopores on the surface for serving as a ‘Host’ for the Pdo-nanoparticles which were prepared in situ by loading of K2PdCl4 through incipient wetness impregnation technique followed by reduction with hydrazine hydrate. The Powder-XRD, SEM-EDX, TEM, N2 adsorption, XPS, etc. analyses were carried out to characterize the stabilized nanoparticles as well as the support. The TEM study reveals that the evenly distributed Pdo-nanoparticles are below 10nm size and exhibit face centred cubic (fcc) lattice geometry. The supported Pdo-nanoparticles exhibit efficient heterogeneous catalytic performance for the Suzuki–Miyaura coupling reactions between different organoboronic acids and aryl halides for preparing the cross-coupling products in 94% isolated yield (maximum) and 100% selectivity in water under ligand free conditions. The nanocatalysts could be recycled at least three consecutive runs with a little loss of their catalytic activities.