Asymmetric Catalytic Aminoalkylations: New Powerful Methods for the Enantioselective Synthesis of Amino Acid Derivatives, Mannich Bases, and Homoallylic Amines

Abstract

Modern methodologies such as the design of chiral catalysts using combinatorial techniques play a key role in the development of asymmetric aminoalkylations. Thus, powerful enantioselective syntheses for many attractive target compounds using chiral Lewis acid or base catalysts like 1 or 2 were created.

Mannich-Type Reactions of Nitrones, Oximes, and Hydrazones

“…This effort has led to new catalytic Mannich reactions, particularly in their asymmetric versions. [16][17][18][19][20][21][22] Several examples of asymmetric catalytic metal-mediated Mannich reactions have been reported [23][24][25] and, more recently, highly efficient asym-metric organocatalytic approaches have become an important research goal. [26][27][28][29][30] Despite the intensity of these efforts, less attention has been paid to Mannich reactions of other C=N-functionalized substrates, such as nitrones, oximes, and hydrazones, which can also act as electrophiles in this process to generate products containing nitrogen functionality in an intermediate oxidation state, that is, as hydroxyamino and hydrazino derivatives (Scheme 1).…”

Preparation of β-Aminoketone by 2,3-Dichloro-5,6-Dicyanobenzoquinone Catalysed Three-Component Mannich Reaction

“…The Mannich reaction represents one of the most important methods for the preparation of natural products and biologically active nitrogencontaining compounds, including β-amino acids, aldehydes and ketones. [1][2][3][4] Three-component Mannich reactions are important in organic synthesis and are used for making intermediates, since several components can be introduced in a single step into a molecule.…”