Heterogeneous copper-free Sonogashira coupling reaction catalyzed by a reusable palladium Schiff base complex in water

Heterogeneous Sonogashira coupling of terminal alkynes with aryl halides was studied over a polymer-supported macrocyclic Schiff base palladium complex. The cross-coupling reaction proceeded smoothly by adding a piperidine in water medium. The catalyst exhibited effective catalytic activities to afford the corresponding products in good to excellent yields under copper-free conditions. Furthermore, the catalyst could be easily recovered and reused for several times without a significant loss of its activity.

Heterogeneous Sonogashira coupling of terminal alkynes with aryl halides was studied over a polymer-supported macrocyclic Schiff base palladium complex. The cross-coupling reaction proceeded smoothly by adding a piperidine in water medium. The catalyst exhibited effective catalytic activities to afford the corresponding products in good to excellent yields under copper-free conditions.Figure optionsDownload as PowerPoint slideHighlights
► Efficient heterogeneous catalyst for the Sonogashira reactions was prepared.
► Polymer-supported Schiff base palladium complex is active for the copper-free reaction in water.
► The catalyst can be reused several times without a significant loss in its activity.