Tridentate SCS palladium(II) complexes: New, highly stable, recyclable catalysts for the heck reaction Academic Article uri icon


  • A new pincer-type SCS ligand containing Pd(II) is a simple, robust catalyst for Heck chemistry using a variety of alkene acceptors and aryl iodides. It is less active with aryl bromides. While certain palladium(II) species insert slowly into the aryl C-H bond of an unsubstituted version of this ligand, the introduction of activating groups into the 5 position of the aromatic ring readily allows quantitative metal insertion. These ligands were synthesized and attached to soluble polymers by simple modification of inexpensive starting materials. For example, both 5-oxy and 5-amido SCS ligands were successfully appended to 5000 M(n) poly(ethylene glycol) via ether or amide linkages, respectively. Both the 5-oxo and 5-amido complexes are active as Heck catalysts in DMF solution in air. The PEG-bound 5-amido- SCS-Pd complex was recycled via solvent precipitation three times with no observed catalyst deactivation. While the 5-amido-SCS-Pd complexes are very robust, their 5-oxo counterparts decompose slowly under certain conditions. These SCS catalysts are analogous to PCP-type catalysts previously reported in the literature but avoid the requirement of an air-sensitive phosphine synthesis.

published proceedings


altmetric score

  • 6

author list (cited authors)

  • Bergbreiter, D. E., Osburn, P. L., & Liu, Y. S.

citation count

  • 257

complete list of authors

  • Bergbreiter, DE||Osburn, PL||Liu, YS

publication date

  • October 1999