Design and Synthesis of an Au@MIL-53(NH2) Catalyst for a One-Pot Aerobic Oxidation/Knoevenagel Condensation Reaction

摘要

Highly dispersed gold nanoparticles were deposited on an amino-functionalized Al-based MIL-53 metal-organic framework by a facile adsorption/reduction strategy. The aromatic amino groups were utilized for adsorption and stabilization of AuCl4- and as basic catalytic sites in the Knoevenagel reaction. The bifunctional Au@MIL-53(NH2) catalyst was utilized to develop an efficient one-pot aerobic oxidation of alcohols/Knoevenagel condensation reaction that takes advantage of Au-0 and NH2 incorporation at the same time. The roles of Au and NH2 groups were systematically investigated to elucidate their functionality during the one-pot reaction. In addition, the Au@MIL-53(NH2) catalyst can be easily recycled up to five times without leaching of the active centres or significant loss of catalytic activity.