Swiss Science Concentrates

L. Wu, L. Falivene, E. Drinkel, S. Grant, A. Linden, L. Cavallo, and R. Dorta*, Angew. Chem. Int. Ed. 2012, 51, 2870 University of Zürich, University of Western Australia N-heterocyclic carbene (NHC) ligands are well-established as an effective ligand motif in organometallic chemistry and catalysis. Due to inherent structural design constraints it has so far proven challenging to create chiral NHCs whose corresponding complexes induce very high enantiomeric excesses in catalytic transformations. One particular design was employed in Pdmediated direct asymmetric α-arylation for the generation of fluorinated oxindoles, a hitherto unexplored reaction. The resulting fluorine-substituted quarternary stereocenters are produced with excellent enantioselectivity. An interesting feature of the ligand, which can in principle exist as a mixture of atropisomers, consists in the easy synthetic access of the single diastereomeric form used in catalysis.