Acknowledgment. We thank the National Science Foundation and the Air Force Office of Scientific Research for generous financial support of this work. ... (43) Weiss, R.; Kolbl, H. J. Am. Chem. SOC. 1975, 97, 3224-3225. ... Bridgehead Solvolytic Reactivity. A Unified Data Set To Test Molecular Mechanics ... Department of Chemistry, University College of Swansea, Singleton Park, Swansea SA2 8PP, UK ... Reactions at bridgehead carbon provide a unique op- ...