Zinc Enolates: The Reformatsky and Blaise Reactions

The Reformatsky reaction, the reaction of α-halo carbonyl compounds with carbonyl compounds in the presence of zinc, has been widely employed for the synthesis of highly functionalized molecules. This reaction is profoundly influenced by the generation of zinc enolate, which sometimes requires preactivation of zinc using TMSCl, microwave, mechanochemical protocols or radical processes. In the last years, several examples using aldehydes, ketones and imines have been described including new stereoselective reactions for the asymmetric syntheses of chiral compounds. Moreover, the generated zinc enolate can react with nitriles, known as the Blaise reaction, which has been also established as a powerful procedure to synthesize a huge number of nitrogen containing compounds. Consequently, the Reformatsky and Blaise reactions have been applied in the synthesis of natural products and drugs. In this chapter, the recent advances in the Reformatsky and Blaise reactions are reviewed.