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.
Amino Acids
; 45(5): 1017-33, 2013 Nov.
Article
em En
| MEDLINE
| ID: mdl-24043459
ABSTRACT
This review provides a comprehensive treatment of literature data dealing with asymmetric synthesis of α-amino-ß-hydroxy and α,ß-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.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Bases de Schiff
/
Aminoácidos
/
Glicina
/
Níquel
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article