Synthesis of beta-substituted alpha-amino acids with use of iridium-catalyzed asymmetric allylic substitution.
The asymmetric synthesis of beta-substituted alpha-amino acids with use of iridium-catalyzed allylic substitution was described. The Ir-catalyzed allylic substitution of diphenylimino glycinate with allylic phosphates proceeded smoothly even at 0 degrees C and gave branch products with high enantioselectivity (up to 97% ee), when chiral bidentate phosphite bearing the 2-ethylthioethyl group was employed. In addition, both diastereomers of the branch products were synthesized stereoselectively by simply switching the base employed. These methods were also applied to the asymmetric synthesis of quaternary alpha-amino acids.
Kanayama
Takatoshi
T
Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
Yoshida
Kazumasa
K
Miyabe
Hideto
H
Kimachi
Tetsutaro
T
Takemoto
Yoshiji
Y
D000478:Alkylation; D000498:Allyl Compounds / Q000138:chemical synthesis*; D000596:Amino Acids / Q000138:chemical synthesis*; D002384:Catalysis; D007495:Iridium / Q000737:chemistry*; D008968:Molecular Conformation; D017905:Phosphites / Q000737:chemistry; D013237:Stereoisomerism
D000498:Allyl Compounds; D000596:Amino Acids; D017905:Phosphites; D007495:Iridium