1. R. Liang, L. Yan, J. Loebach, M. Ge, N. Horan, J. Gildersleeve, C. Thompson, A. Smith K. Biswas, D. Kahne, Department of Chemistry, Princeton University, Princeton, NJ 08544, USA.
2. Y. Uozumi, K. Sekanina, W. C. Still, Department of Chemistry, Columbia University, New York, NY 10027, USA.