Eu2O3 modified CeO2 nanoparticles as a heterogeneous catalyst for an efficient green multicomponent synthesis of novel phenyldiazenyl-acridinedione-carboxylic acid derivatives in aqueous medium†
Abstract
A green and highly efficient protocol has been developed for the synthesis of phenyldiazenyl-acridinedione-carboxylic acids by a one-pot multicomponent coupling of 1,3-dicarbonyl compounds, 4-hydroxy-3-methoxy-5-(substituted-phenyl-diazenyl)-benzaldehydes and glycine using europium modified ceria nanoparticles as the catalyst in aqueous medium. An environmentally benign reaction procedure, a wide diversity of products, excellent yields and reusability of the catalyst make the present method extremely advantageous for the synthesis of phenyldiazenyl-acridinedione-carboxylic acids. The formation, size and oxidation state of the metal ions present in the nano-europium modified ceria is confirmed by powdered-XRD, TEM and XPS techniques.