title: Asymmetric synthesis of α-amino acids via homologation of Ni(II) complexes of glycine Schiff bases. Part 2: aldol, Mannich addition reactions, deracemization and (S) to (R) interconversion of α-amino acids.
abstract: This review provides a comprehensive treatment of literature data dealing with asymmetric synthesis of α-amino-β-hydroxy and α,β-diamino acids via homologation of chiral Ni(II) complexes of glycine Schiff bases using aldol and Mannich-type reactions. These reactions proceed with synthetically useful chemical yields and thermodynamically controlled stereoselectivity and allow direct introduction of two stereogenic centers in a single operation with predictable stereochemical outcome. Furthermore, new application of Ni(II) complexes of α-amino acids Schiff bases for deracemization of racemic α-amino acids and (S) to (R) interconversion providing additional synthetic opportunities for preparation of enantiomerically pure α-amino acids, is also reviewed. Origin of observed diastereo-/enantioselectivity in the aldol, Mannich-type and deracemization reactions, generality and limitations of these methodologies are critically discussed.
authors.affiliation: Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, 20018, San Sebastián, Spain, sorochinsky.a@gmail.com.
authors.forename: Alexander E
authors.initials: AE
authors.lastname: Sorochinsky
authors.forename: José Luis
authors.initials: JL
authors.lastname: Aceña
authors.forename: Hiroki
authors.initials: H
authors.lastname: Moriwaki
authors.forename: Tatsunori
authors.initials: T
authors.lastname: Sato
authors.forename: Vadim
authors.initials: V
authors.lastname: Soloshonok
mesh_terms: D000596:Amino Acids / Q000138:chemical synthesis* / Q000737:chemistry; D005998:Glycine / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry*; D012545:Schiff Bases / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D012545:Schiff Bases; D009532:Nickel; D005998:Glycine