Bimetallic Pdxni1-X and Pdxco1-X Nanoparticles Supported on K-Oms Highly Active, Environmentally Friendly and Reusable Nanocatalysts for the Suzuki–miyaura Cross-Coupling Reactions in Water

Abstract

Addressed herein is the catalysis of bimetallic PdxNi1-x and PdxCo1-x nanoparticles (NPs) supported on a cryptomelane-type manganese oxide (K-OMS-2) solid for the Suzuki–Miyaura cross-couplings of phenylboronic acid with various aryl halides. Bimetallic PdxNi1-x and PdxCo1-x NPs were prepared by using a conventional one-step impregnation–reduction method. Among these catalysts with different compositions of Ni and Pd or Co and Pd, the Pd0.2Ni0.8 and Pd0.2Co0.8 catalysts showed the highest activity in the Suzuki–Miyaura cross-couplings of various aryl halides including iodides, bromides, and even chlorides with phenylboronic acid in ambient air and water under reflux conditions. The Suzuki–Miyaura cross-coupling reaction proceeded efficiently in the presence of Pd0.2Ni0.8@K-OMS-2 and Pd0.2Co0.8@K-OMS-2 NPs under the optimized conditions in water. Pd0.2Ni0.8@K-OMS-2 and Pd0.2Co0.8@K-OMS-2 NPs provided high conversions up to 98% and 99% and turnover frequencies of 11,760 and 11,880 h−1 in the cross-coupling of phenylboronic acid with 1-bromo-4-nitrobenzene. More importantly, these new supported Pd0.2Ni0.8@K-OMS-2 and Pd0.2Co0.8@K-OMS-2 NPs were found to be highly durable nanocatalyst throughout the reusability experiments, and they maintain almost their inherent activity after 10th and 5th catalytic cycle, respectively. Bimetallic Pd0.2Ni0.8@K-OMS-2 and Pd0.2Co0.8@K-OMS-2 NPs were characterized by Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), scanning electron microscopy with energy dispersive X-ray (SEM-EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and ICAPQ inductively coupled plasma mass spectroscopy (ICP-MS) analyses. © 2020 John Wiley & Sons, Ltd.