RESUMO
To All(oc) involved: A palladium-catalyzed formal 5-endo-trig heteroannulation of enones generated in situ from amino acid derived ß-keto nitriles has been realized (see scheme; Alloc=allyl carbamate). The reaction proceeds with allyl-group transfer from the carbamate protecting group to generate two new contiguous stereocenters, including one quaternary center, with high selectivity.
RESUMO
The vicinal amino alcohol is a common motif in natural products and pharmaceuticals. Amino acids constitute a natural, inexpensive, and enantiopure choice of starting material for the synthesis of such functionalities. However, the matters concerning diastereoselectivity are not obvious. This Perspective takes a look in the field of diastereoselective synthesis of vicinal amino alcohols starting from amino acids using various methods.
Assuntos
Amino Álcoois/síntese química , Glucosídeos/química , Pirimidinonas/química , Aldeídos/síntese química , Estrutura Molecular , Oxirredução , EstereoisomerismoRESUMO
Herein a practical and scalable route to 1-deoxyaltronojirimycin is presented. The target is achieved in 9 steps and 43% yield featuring only two chromatographic purifications.
Assuntos
1-Desoxinojirimicina/análogos & derivados , 1-Desoxinojirimicina/síntese química , Alquilação , Estrutura Molecular , Oxirredução , Fatores de TempoRESUMO
The mildness and low basicity of vinylzinc species functioning as a nucleophile in addition to alpha-chiral aldehydes is characterized by lack of epimerization of the vulnerable stereogenic center. This is demonstrated by a highly diastereoselective synthesis of 1-deoxygalactonojirimycin in eight steps from commercial starting materials with overall yield of 35%.