Pd NPs supported on halloysite functionalized with Schiff base as an efficient catalyst for Sonogashira reaction.

A hybrid system was designed and synthesized through reacting modified halloysite (Hal-Cl) with Schiff base (DAB-PC) and applied as catalytic support for anchoring Pd NPs to afford Pd@Hal-DAB-PC catalyst. The resultant material was well identified by various analyses including Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction patterns (XRD), thermogravimetric analysis (TGA), field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and inductively coupled plasma-optical emission spectrometry (ICP-OES) and revealed outstanding catalytic activity in the Sonogashira reaction in aqueous media. Also, This nanocatalyst was simply collected and recycled up to six runs with a slight drop in efficiency, indicating the durability of Pd@Hal-DAB-PC.