A dithizone-functionalized polystyrene resin-supported Pd(II) complex as an effective catalyst for Suzuki, Heck, and copper-free Sonogashira reactions under aerobic conditions in water

A novel polystyrene-supported palladium(II) dithizone complex is found to be a highly active catalyst for the Suzuki, Heck, and Sonogashira reactions of aryl halides in water. By this protocol, aryl halides, coupled with phenyl boronic acid (Suzuki reaction), alkenes (Heck reaction) or terminal alkyne (Sonogashira reaction), smoothly affords the corresponding cross-coupling products in good to excellent yields. Furthermore, the catalyst shows good thermal stability and recyclability. The catalyst was recycled for the Suzuki, Heck, and Sonogashira reactions for five runs without appreciable loss of its catalytic activity and negligible metal leaching.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (78 K)Download as PowerPoint slideHighlights► Highly efficient heterogeneous catalyst for the Suzuki, Heck and Sonogashira reactions were prepared. ► The procedure is easy and does not require special precautions. ► [PS-dtz-Pd(II)] was fully characterized. ► The catalyst can be reused several times without a noticeable change in activity.