In this study, 9-(diphenylphosphanyl)[7]helicene was prepared as a suitable ligand for the subsequent synthesis of palladium complexes. The corresponding PdL2Cl2 complex was then successfully obtained in both racemic and enantiopure forms. The PdL2Cl2 complex emerges exclusively in the trans arrangement showing dynamic interconversion between its homo- and heterochiral forms as evidenced by 31P NMR. The trans arrangement was ultimately confirmed by X-ray crystallography using single crystals of the homochiral complex. Additionally, the PdL2Cl2 complex was subjected to screening of its catalytic activity in a Suzuki-type reaction of aryl bromides with aryl boronic acids showing fair yields of the resulting biaryls. However, the final asymmetric reactions catalyzed by the optically pure PdL2Cl2 complex provided targeted binaphtyls only in negligible enantiomeric excess.

Department of Inorganic Chemistry Faculty of Science Charles University Prague Hlavova 2030 128 40 Prague 2 Czech Republic

Department of Organic Chemistry University of Chemistry and Technology Prague Technická 5 166 28 Prague 6 Czech Republic

Institute of Chemical Process Fundamentals v v i The Czech Academy of Sciences Rozvojová 1 135 165 02 Prague 6 Czech Republic

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