Selective synthesis of δ-lactone via palladium nanoparticles-catalyzed telomerization of CO2with 1,3-butadiene

Abstract

An efficient method for the selective synthesis of δ-lactone from carbon dioxide and 1,3-butadiene was developed using palladium nanoparticles as the catalyst without any additional ligand. The highest yield (51% with 94% selectivity) was achieved using Pd(acac)2as the precatalyst in the presence of TBAAc as both reducing and stabilizing agent in acetonitrile at 70 °C. The palladium nanoparticles generated in situ could be easily recovered through a simple extraction process and reused three times without an obvious loss in activity. The TEM image showed the presence of (3.8 ± 1.1) nm-sized palladium nanoparticles in the reaction mixture.