Microwave-Assisted Catalytic Acetylation of Alcohols by Gold-Nanoparticle–Supported Gadolinium Complex

A gold nanoparticle (AuNP)–supported gadolinium complex (RS-Au-L-Gd) catalyst was prepared through simple chelation of GdCl₃ to the surface-bound spacer, 1,4,7-tris(carboxymethyl)-10-(11-mercaptoundecyl)-1,4,7,10-tetraazacyclododecane (HSDO3A). This AuNP-supported Gd complex was found to be a highly effective catalyst for the acetylation of various alcohols and phenol in the presence of acetic anhydride. With a loading of 0.4 mol% of RS-Au-L-Gd, the almost complete transformation can be achieved in 60 s under microwave irradiation conditions. This hybrid catalyst was air stable, water soluble, dissolvable in many organic media, and precipitable. It can be readily recycled more than eight times without any significant loss of its catalytic activity.