More Than Just Sweet - Sugar-Derived Stereodifferentiating Agents for Asymmetric Synthesis

Abstract

S u g a r s f o r A s y m m e t r i c S y n t h e s i sAbstract: Stereodifferentiating agents such as chiral auxiliaries, reagents and additives as well as ligands for metal catalysis and organocatalysts are essential in asymmetric synthesis. While it is commonly agreed that amino acids, terpenes and alkaloids from the chiral pool make highly useful starting materials for many important stereodifferentiating agents, carbohydrates, which are the most abundant chiral natural products, are still regularly regarded as illsuited for this purpose. Many chemists are surprisingly ignorant of the wealth of carbohydrate-derived agents available for stereoselective synthesis. This review highlights the most successful carbohydrate-derived auxiliaries, reagents, complex ligands and organocatalysts, and provides an overview of their usefulness in asymmetric transformations.

A versatile and efficient approach for the synthesis of chiral 1,3-nitroamines and 1,3-diamines via conjugate addition to new (S,E)-γ-aminated nitroalkenes derived from L-α-amino acids

“…Nonetheless, the use of chiral nitroalkenes bearing a stereogenic center in the γ-position in nonracemic diastereoselective syntheses ("chiron" approach [45]) is less frequent in the literature. Notably, chiral nitroalkenes derived from carbohydrates [46–50] have been most often utilized as "chirons" in diastereoselective syntheses. Most nitroalkenes are synthesized from a nitroaldol product followed by elimination of the activated hydroxy group in the sulfonate or acetate form [51] although various routes have often been applied [52–54].…”