1. For a review, see: Wasserman, H. H.; Berahl, D. R.; Lu, T. J. In The Chemistry of Cyclopropyl Group; Rappoport, Z., Ed.; John Wiley & Sons: New York, 1987; Part 2, p. 1455.
2. Matlin, A. R.; Lahti, P. M.; Appella, D.; Straumanis, A.; Lin, S.; Patel, H.; Jin, K.; Schrieber, K. P.; Pauls, J.; Raulerson, P. J. Am. Chem. Soc. 1999, 121, 2164; Hess Jr., B. A.; Eckart, U.; Fabian, J. J. Am. Chem. Soc. 1998, 120, 12 310; Sorensen, T. S.; Sun, F. Can. J. Chem. 1997, 75, 1030; Hrovat, D. A.; Rauk, A.; Sorensen, T. S.; Powell, H. K.; Borden, W. T. J. Am. Chem. Soc. 1996, 118, 4159; Sorensen, T. S.; Sun, F. J. Am. Chem. Soc. 1995, 117, 5592; Lim, D.; Hrovat, D. A.; Borden, W. T.; Jorgensen, W. L. J. Am. Chem. Soc. 1994, 116, 3494, and references cited therein.
3. Wasserman and co-workers have reported that β-lactams can be prepared by the nitrogen-inserting ring expansion of cyclopropanones: Wasserman, H. H.; Adickes, H. W.; Ochoa, O. E. J. Am. Chem. Soc. 1971, 93, 5586; Wasserman, H. H.; Baird, M. S. Tetrahedron Lett. 1971, 3721; Wasserman, H. H.; Cochoy, R. C.; Baird, M. S. J. Am. Chem. Soc. 1969, 91, 2375.
4. It is well known that cyclopropanone hemiacetals are useful three-carbon fragments in organic synthesis: Salaün, J. R. Y. In Small Ring Compounds in Organic Synthesis III; Meijere, A., Ed.; Springer-Verlag: Berlin, 1988; p. 1; Kuwajima, I.; Nakamura, E. In Small Ring Compounds in Organic Synthesis IV; Meijere, A., Ed.; Springer-Verlag: Berlin, 1990, p. 1, and references cited therein.
5. Fedorenko, E. N.; Zaitseva, G. S.; Baukov, Y. I.; Lutsenko, I. F. Zh. Obshch. Khim. 1986, 56, 2431; Zaitseva, G. S.; Novikova, L. I.; Livantsova, L. I.; Kisin, A. V.; Baukov, Y. I. Zh. Obshch. Khim. 1990, 60, 1073.