Successive oxidation–condensation reactions using a multifunctional gold-supported nanocomposite (Au/MgCe–HDO)†
Abstract
The application of gold-supported nanocomposites is useful in clinical diagnostics because of their ability to provide bio-compatible and sensitive detection systems. A gold-supported magnesium hydroxide and cerium oxide nanocomposite framework (Au/MgCe–HDO) was synthesized and characterized via XRD, XPS, SEM, DLS, TEM, and TGA techniques. The nanocomposite was used as a selective catalyst for the aerobic oxidation of alcohols under mild reaction conditions followed by successive condensation reactions, like Knoevenagel and Claisen–Schmidt condensation. Substituted benzyl alcohols were converted into the corresponding carbonyl compounds in the presence of the Au/MgCe–HDO nanocomposite with O2 gas and toluene as a solvent. We observed that, upon the addition of malononitrile/ethyl cyanoacetate/acetophenone to the catalyst in the aerobic oxidation reaction, the reaction proceeds to produce the corresponding desired condensation product with up to 95% yield.