1. For reviews of multicomponent reactions: Ugi, I.; Domling, A.; Ebert, B. Combinatorial Chem. 1999, 125; Ugi, I. Pure and Appl. Chem. 2001, 73, 187; Domling, A.; Ugi, I. Angew. Chem., Int. Ed. Engl. 2000, 39, 3168.
2. For examples of high pressured promoted multicomponent reactions: Mannich reaction; Matsumoto, K. Angew. Chem., Int. Ed. Engl. 1982, 21, 922; Matsumoto, K.; Uchida, T.; Hashimoto, S.; Iida, H.; Otani, S. Heterocycles 1993, 36, 2215. Ugi reaction; Yamada, T.; Yanagi, T.; Omote, Y.; Miyazawa, T.; Kuwata, S.; Sugiura, M.; Matsumoto, K. J. Chem. Soc., Chem. Commun. 1990, 1640. Passerini reaction; Yamada, T.; Motoyama, N.; Taniguchi, T.; Kazuta, Y.; Miyazawa, T.; Kuwata, S.; Matsumoto, K.; Sugiura, M. Chem. Lett. 1987, 723; Jenner, G. Tetrahedron Lett. 2002, 43, 1235. Domino–Horner–Wadsworth–Emmons–Michael reaction; Has-Becker, S.; Bodmann, K.; Kreuder, R.; Santoni, G.; Rein, T.; Reiser, O. Synlett 2001, 1395.
3. For a review, Duthaler, R. O. Tetrahedron 1994, 50, 1539.
4. For the most recent example: Vachal, P.; Jacobsen, E. N. J. Am. Chem. Soc. 2002, 124, 10012 and references cited therein.
5. Ueber Uroxansäure und die chemische Constitution der Harnsäure