The focus of this research will be the development of new synthetic methodology using diradical chemistry. Atom transfer chemistry of trimethylenemethane (TMM) diyls, (4+3) - cycloadditons to TMM diradicals and fragmentation/cyclization of vinylcyclopropyl substituted TMM diyls will be probed. Appropriate synthetic targets have been chosen to showcase the methodology. With this renewal award, the Synthetic Organic Program is supporting the research efforts of Dr. R. Danial Little of the Department of Chemistry at the University of California, Santa Barbara. Professor Little will focus his work on developing three processes involving diradicals. Atom transfer reactions, reactions with 1,3-dienes and fragmentation-cyclization reactions will all be explored in order to develop new methodology for the construction of interesting natural products.