An efficient synthesis of a,aʹʹ-benzylidene bis(4-hydroxycoumarin) derivatives catalyzed by Tl2O3 nanoparticles

In this work, we attempted to synthesize thallium (III) oxide nanostructures by direct thermal decomposition using thallium I phenylsuccinic acid coordination polymer [Tl(PsucH)]n as a precursor. Also, Tl2O3 nanoparticles have been characterized by scanning electron microscopy (SEM), X-Ray powder diffraction (XRD) and IR spectroscopy and then we report a simple and efficient method for the synthesis of ?,??-benzylidene bis(4-hydroxycoumarin) derivatives by aromatic aldehyde and 4-hydroxycoumarin by using Tl2O3 nanoparticles in H2O/EtOH at room temperature. A wide spectrum of functional groups, were tolerated in the developed protocol. The target molecules were obtained in good to excellent yield applying the current method. The catalyst can be recover for the subsequent reactions and reused without loss of activity.