This project in the Inorganic, Bioinorganic and Organometallic Chemistry Program is in the area of organometallic chemistry. The focus of the project is metallacycle complexes which play an important role as intermediates in numerous organometallic reactions such as cycloadditions of alkynes and olefin metathesis. The goal is the development of new transition metal-mediated cyclizations involving a carbene moiety and two equivalents of alkyne. Such a reaction is fundamentally different than the Pauson-Khand reaction and would ultimately allow for novel intramolecular cyclizations in which acyclic precursors are converted to fused tricyclic ring systems. The general approach will involve the formation of a metallacyclopentadiene-carbene intermediate either by the introduction of a carbene or carbene precursor onto a metallacyclopentadiene complex, or by the formation of a metallacycle from a complex already containing a carbene precursor. The development of an efficient cycloaddition reaction of the type under investigation would simplify greatly the laboratory synthesis of a wide variety of biologically important organic compounds.
