Green synthesis and characterization of silver nanoparticles (Ag NPs) from extract of plant Radix Puerariae: An efficient and recyclable catalyst for the construction of pyrimido [1,2-b] indazole derivatives under solvent-free conditions

We have developed a green and environmentally friendly approach for the synthesis of silver nanoparticles (Ag NPs) using Radix Puerariae plant extract via a novel chemical route. The prepared Ag NPs has been characterized by TEM, XRD, SEM, DLS, EDX, and UV-Vis. Further, catalytic application of this fascinating nanomaterial has been utilized in the synthesis of biologically important pyrimido [1,2-b]indazole derivatives via one-pot three component coupling reaction between aldehydes, alkynes and amines with excellent yields under solvent-free conditions. After completion of the catalytic reaction, the Ag NPs could be easily recovered and reused for four times without significant loss in its catalytic activity.