Gold catalysis and new chiral NHC ligands.

Gold catalysis of organic reactions has become a rapidly expanding field in recent 5 years after being neglected by organic chemists for a long time. Gold complexes are less oxophilic than other common Lewis acids, but they are highly reactive as Lewis a cids towards carbon-carbon multiple bonds. Gold catalysts can therefore react in a very selective way and give access to highly complex molecules. The present project describes the investigation of new gold catalysed cyclisation reactions of diynes. NHC (N-Heterocyclic Carbene) ligands are electron-rich N,N-disubstituted imidazol-2-ylidenes developed the last decade due to their attractive properties. In particular, they play a favourable role in transition metal catalyzed reactions, replacing the tradit ional phosphine ligands. We will design and prepare a number of new chiral NHC ligands, based on suitable approaches for such syntheses. A collaboration with a research group at the Universities of Hamburg has been established.