The conversion of a variety of well‐known test reactions, representing the key reactivity patterns of gold catalysis, were analyzed by GC and 1H NMR. The study is focused on establishing of a strategical approach for the consideration of ligand influence and counter anion influence during the catalyst optimization including an industrial perspective. The study shows a dominance of the counter anion, a dominance which up to now has been neglected in most of the routine screenings. In addition, a drastic substrate‐dependency became obvious, even a marginal variation of the substrate already could strongly effect the catalytic activity and change the optimal counter anion or ligand. Based on the collected data a strategic concept for an efficient screening for a specific substrate is introduced, this concept can serve as an important guideline for catalyst optimization in homogeneous gold catalysis.magnified image

A comparison of versatile counter anions was investigated by means of a variety of well‐known test reactions representing the key reactivity patterns of homogeneous gold catalysis, the catalytic activity was monitored by GC and 1H NMR. As previously reported, the counter anion influence is usually more pronounced than the corresponding ligand effect. Due to this, the study is focused on the investigation of counter anions so far not included from investigation of homogeneous gold‐catalyzed reactions. The examinations using so far neglected counter anions (BArF4)−, [B(C6F5)4]−, [Al(OC(CF3)3)4]− and [B(C6F5)3(OAcF)]− showed surpassing or at least similar catalytic activities as the commonly used counter anions. The expanded use of counter anions can occupy an important role in future concerning catalyst optimization in gold catalysis.magnified image

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Unusual platinum(II) trimetalated derivatives have been synthesized and characterized by reaction of cis-[Pt(R) 2 (DMSO) 2 ] (R ) Me, Ph) and 6-phenyl-2,2′bipyridine. The behavior of the substituted 2,2′-bipyridine as a threefold-deprotonated ligand is unprecedented.

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