Overview: Our research centers on the enantioselective synthesis of complex, physiologically active natural products. To this end, we are interested in developing new organic reactions, as illustrated by our current work with intramolecular alkylidene carbene insertion, and the total synthesis of (+)-cassiol 1 . We are also interested in using computational organometallic chemistry to understand catalysis, as exemplified by our recent analysis of diastereoselectivity in Rh-mediated intramolecular C-H insertion, leading to the synthesis of the Dendrobatid alkaloid 251F 2. Using this same computational approach, we have developed a model that effectively predicts both the kinetic and the thermodynamic product from intramolecular cyclozirconation of a diene. This work laid the foundation for the total synthesis of (-)-haliclonadiamine 3.