9308105 Pearson The focus of this research is the development of new methods for carbon-carbon bond formation using a variety of organoiron complexes. There are four specific aspects of organoiron chemistry that will be studied. The first aspect investigates new protocols for the generation of free radicals from dienyliron complexes and their intramolecular coupling with pendant olefinic groups to form carbocyclic ring systems. This represents the first application of organometallic free radicals in synthetically useful processes. The second aspect studies extensions and applications of iron-promoted carbonylative annulation of diynes and enynes for formation of cyclopentadienoneiron complexes and cyclopentenones. The third area explores intramolecular carbon nucleophile additions to cyclohexadienyliron cations to provide important new methods for the construction of densely functionalized molecules. The final aspect exploits the ability of an organoiron moiety to control stereochemistry during multiple functionalization of eight-membered rings, which are traditionally difficult to handle; the use of organometallic chemistry provides solutions to problems of conformational and stereochemical control. %%% With this award, the Synthetic Organic Program is supporting the research of Dr. Anthony J. Pearson of the Department of Chemistry at Case Western Reserve University. Professor Pearson will focus his work in the area of synthetic methodology developing new methods for carbon-carbon bond formation using a variety of organoiron complexes. ***