Enantioselective Nickel-Catalysed Transformations
The first chapter of the book concentrates on the new developments achieved since the beginning of 2004 in asymmetric nickel-catalysed cycloaddition reactions, well demonstrating that this field constitutes an important tool for organic synthesis related to impressive progress made in the last decade in expanding this chemistry. Indeed, in the last 10 years a range of chiral nickel complexes, predominantly based on various nitrogen-containing chelating ligands, have been successfully applied as highly efficient catalysts in various enantioselective cycloadditions, including many 1,3-dipolar cycloadditions, various Diels–Alder cycloadditions, and other cycloadditions. The asymmetric 1,3-dipolar cycloaddition reaction, which is undoubtedly one of the most important methods for the construction of chiral five-membered rings, is the reaction that has known the most developments in the last decade, with high levels of stereocontrol which is extremely important for constructing heterocyclic compounds from the viewpoint of the synthesis of biologically active compounds. In addition, several excellent results have been published in the area of enantioselective nickel-catalysed Diels–Alder cycloadditions, and various other interesting nickel-catalysed asymmetric cycloadditions, such as [2 + 2 + 2] cycloaddition reaction of two molecules of isocyanates with allenes, and [3 + 3] cycloaddition of nitrones with 2-substituted cyclopropane-1,1-dicarboxylates, have been recently successfully achieved.