Versatile Scorpionates—New Developments in the Coordination Chemistry of Pyrazolylborate Ligands

Abstract

Much more versatile than previously anticipated are the coordination modes of tris(pyrazolyl)borate ligands (scorpionates). Recent contributions in this area not only lead to a new understanding of the electronic effects, but for the first time report unusually high and low hapticities as well as novel coordination modes such as the π coordination of a pyrazolyl ring to potassium (see structure). Potentially useful new ligands have been made available through innovative synthetic routes.