MAPPING FLUOROAROMATIC SUBSTITUENT EFFECTS IN ORGANOMETALLIC CHEMISTRY FROM OLEFIN POLYMERIZATION KINETICS TO MOLECULAR ARCHITECTURE AND CRYSTAL ENGINEERING

Professor Paul Deck, Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia

abstract

We have developed methods for preparing cyclopentadienyl (Cp) ligands bearing one through four pentafluorophenyl substituents. This is the first family of Cp ligands to have highly electron-withdrawing substituents that are chemically stable toward a wide variety of synthetic reagents and reaction conditions. We have exploited these properties in the first systematic analysis of the effects of electron-withdrawing substituents on zirconocene dichloride catalyzed ethylene polymerization. Recently, we have also learned that fluoroaromatic substituents have profound effects on the molecular structure of metallocenes and related compounds because of strong arene stacking and CH...FC hydrogen bonding interactions that are pervasive in the crystal structures of these compounds. Nucleophilic aromatic substitution chemistry also provides routes to new metallocene-containing linear and hyperbranched polymer architectures.

We find ourselves in exciting circumstances, with a project that reveals interesting trends and presents new opportunities on an almost daily basis. In this seminar I hope to convey this enthusiasm while demonstrating the wide-ranging utility of fluoroaromatic compounds in organometallic chemistry.