1. (a) Betti, M. Gazz. Chim. Ital. 1900, 30, 310.
2. (b) Betti, M. Gazz. Chim. Ital. 1901, 31, 377.
3. (c) Betti, M. Gazz. Chim. Ital. 1901, 31, 170.
4. (a) Palmieri, G. Eur. J. Org. Chem. 1999, 805. (b) Palmieri, G. Tetrahedron: Asymmetry 2000, 11, 3361. (c) Cimarelli, C.
5. Volpini, E. J. Org. Chem. 2001, 66, 4759. (d) Cimarelli, C.