Synfacts 2007(12): 1275-1275  
DOI: 10.1055/s-2007-991351
Metal-Catalyzed Asymmetric Synthesis and Stereoselective Reactions
© Georg Thieme Verlag Stuttgart · New York

Intramolecular Pauson-Khand Reactions with Ir(phox) Catalysts

Contributor(s): Hisashi Yamamoto, Matthew B. Boxer
Z.-L. Lu, E. Neumann, A. Pfaltz*
University of Basel, Switzerland
Further Information

Publication History

Publication Date:
22 November 2007 (online)


The Pfaltz group has extended their work with phosphane oxazoline (phox) ligands to include asymmetric induction in the Pauson-Khand reaction. Moderate to high ee values were obtained for a limited number of substrates. The main focus of the paper was the optimization of conditions for the reaction. CO pressure, catalyst loading, and counteranion effect were studied. A pressure of 2.2 bar was determined to be the best CO pressure in terms of yield and ee, while tetra­fluoroborate, hexafluorophosphate, and triflate proved to be some of the better counteranions.