Preparation of palladium nanoparticle catalyst in ionic liquid and its catalytic properties for Heck-Mizoroki reaction

A palladium nanoparticle (PdNPs) catalyst was synthesized in halogen-free anion ionic liquid (1-buthyl-3-methylimidazolium lactate, [Bmim]Lac) by a simple chemical approach. The transmission electron microscopy analysis confirmed the presence of highly dispersed PdNPs in [Bmim]Lac with small average particle size distribution from 2.2 to 3.1 nm. The size of the PdNPs increases with decreasing molar ratio of [Bmim]Lac to Pd(OAc)2 and increasing temperature. The activity of PdNPs@[Bmim]Lac catalyst was tested by the Heck-Mizoroki reaction, and the conditions were optimized. The catalyst can efficiently catalyze couplings of various aryl bromides and iodides with different olefins, giving good yields of products under the optimal conditions and be recycled up to six consecutive times.

Graphical AbstractA PdNPs@[Bmim]Lac catalyst was prepared using a non-toxic and environmentally benign lactate anion IL as a stabilizer. The catalyst can be used efficiently for the Heck-Mizoroki reaction of various aryl halides with different olefins and can be reused.Figure optionsDownload as PowerPoint slide