6.13 C-C Bond Formation: Cascade or Domino Reaction

Over the past few years, the field of organocatalyzed domino reactions, with particular focus on enantioselective C-C bond forming reactions, has experienced a rapid and impressive development and is now offering a complementary approach to metal and biocatalyzed cascade reactions. Organocatalytic domino reactions possess tremendous advantages over the classical multistep reaction sequences, as they avoid purification of the intermediates and circumvent time consuming protection/deprotection steps and functional group interconversions. In addition, the operational simplicity, the mild reaction conditions, and the ability of the same catalysts to promote several different transformations with remarkable selectivities constitute further noteworthy features of the organocatalyzed domino reactions. The great potential of organocatalyzed domino reactions is proven in the synthesis of a wide variety of cyclic compounds which are of interest for the synthesis of natural products and biologically active compounds.