Today's world is unthinkable without catalysis and efficient catalysts. Although the focus of Organic Chemistry is truly on carbon, catalysis involves in nearly all cases other elements, especially transition metals. In this research project, which is part of the International Research Training Group IRTG 1038 "Catalysis and Catalytic Reactions for Organic Synthesis", we want to investigate two kinds of catalytic processes. The first one deals with the influence of weakly coordinating anions (WCAs) on transition metal, especially gold catalyzed reactions, and the second one is the use of bidentate Lewis acids as catalysts in organic synthesis. Due to constrains in resources only the second part can be realized. The multidisciplinary nature of the problems, ranging from organic synthesis and inorganic chemistry to molecular interactions between complex solvent, catalyst and substrate is re-flected in a joint effort by two groups from the University of Basel, Dr. Hermann Wegner (or-ganic synthesis and catalysis) and Prof. Markus Meuwly (computational and theoretical chem-istry), and one group from the University of Freiburg, Prof. Ingo Krossing (inorganic chemistry). Bidentate Lewis acids have hardly applied as catalysts in organic synthesis up to now. Here, a first proof of principle has been shown in the Wegner group for an Inverse Electron Demanding Diels-Alder (IEDDA) reaction of 1,2-diazene to 1,2-substituted aryl compounds. Using spectroscopic as well as computational tools should clarify the exact mechanism, influences and other parameter on the reaction. By this approach we will shine light on this interesting class of unexplored catalysts and open up the way for optimizing the IEDDA to a general applicable method for the preparation of 1,2-substituted arenes. With a detailed picture of the transformation the knowledge will be used to find other application for bidentate Lewis acids in catalysis, e.g. other challenging cycloaddition reactions or aldol type chemistry. Insights into bidentate Lewis acids as catalysts in organic synthesis will be a benefit for the whole community and stimulate the development greatly in this area. The multidisciplinary approach offers the enormous advantage to tackle the problem from various dimensions. As this research project is part of a ProDoc program it has the great advantage to give the par-ticipating students a deep insight into various disciplines and how to combine them to address questions in catalysis.