The scope of the recently discovered gem-dimethylation reaction based on the Tebbe reagent will be explored. The reaction provides a one step route to the important gem-dimethyl substructure by the direct conversion of a carbonyl group. The substructure is found in many important natural and synthetic products. The work will seek to provide an understanding of the structure, or structures, of the actual active species generated from the titanium-based reagent. The studies will explore the preparation of analogous reagents and will probe the mechanistic pathways for these species. The synthetic scope of the reaction with different types of carbonyl groups will also be explored. %%% With this Research in Undergraduate Institutions (RUI) award, the Organic Synthesis Program is supporting the research of Dr. Stanley H. Pine of the Department of Chemistry at California State, Los Angeles, University. Dr. Pine's work focuses on a new synthetic reaction based on a bimetallic organometallic compound containing titanium and aluminum. The reagent will accomplish, in one step, the transformation of a carbonyl group into a group that contains a carbon bound to two methyl groups, a process that now requires two or more synthetic steps. The development of the reagent will increase the ease and directness of the synthesis of a number of terpenoid natural products. The program will also involve undergraduates in a meaningful way.