Manirul Islam

Polystyrene-Anchored Palladium(II) Schiff Base Complex: A Reusable Catalyst for Phosphine-Free and Copper-Free Sonogashira Cross-Coupling Reaction in Aqueous Medium

Abstract A novel polystyrene-supported palladium(II) complex, an excellent and recyclable catalyst, was synthesized for Sonogashira reactions. The present complex shows high catalytic activity for Sonogashira cross-coupling reaction of aryl halides with phenylacetylene under phosphine-free and copper-free reaction conditions in aqueous (DMF–H2O) medium. The catalyst could be reused for at least six reaction cycles with almost unchanged catalytic properties.

Heterogeneously Catalyzed Phosphine-Free Heck Cross-Coupling Reaction of Aryl Halides with Reusable Palladium(II) Schiff Base Complex

The coupling between aryl halides with terminal alkenes (Heck reaction) has been investigated in the presence of a polystyrene-supported Schiff base palladium(II) catalyst. The present catalyst is air and moisture-stable and has significant catalytic activity in Heck cross-coupling reactions under operating conditions. Various aryl halides and terminal alkenes were coupled smoothly under air, to afford the corresponding cross-coupled products in excellent yields. Furthermore, the catalyst can be easily recovered quantitatively by simple filtration and reused up to seven cycles without losing its activity.