With funding from the Organic Dynamics Program, Professor Streitwieser at the University of California-Berkeley is to continue his studies on the reaction dynamics of polar organometallic reagents. Through experimental as well as theoretical chemistry, a more thorough understanding of the factors governing the aggregation of these complexes and their relative reactivities will be garnered. One of the major questions still confounding investigators in this area is the state of reagent aggregation versus reactivity. This proposal addresses this issue. Since these reagents are ubiquitous in organic synthesis, an understanding that allows scientists to predict the reactivity with regard to chemoselectivity and stereoselectivity would have significant impact on the use. Synthetic organic chemistry which is responsible for new methodologies and actual preparations of physiologically active compounds relies heavily on specific reagents to effect certain organic transformations. Some of these reagents are complex and have a variety of forms. Since the exact form affects the efficiency of its reactivity, it is important to understand the factors influencing these reagents. This proposed effort will address these issues with regard to polar organometallic reagents.