The Julia-Colonna asymmetric epoxidation reaction of chalcone catalyzed bylength defined oligo-L-leucine: Importance of the N-terminal functional group and helical structure of the catalyst in the asymmetric induction

Citation
R. Takagi et al., The Julia-Colonna asymmetric epoxidation reaction of chalcone catalyzed bylength defined oligo-L-leucine: Importance of the N-terminal functional group and helical structure of the catalyst in the asymmetric induction, B CHEM S J, 73(9), 2000, pp. 2115-2121
Citations number
37
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemistry
Journal title
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN
ISSN journal
0009-2673 → ACNP
Volume
73
Issue
9
Year of publication
2000
Pages
2115 - 2121
Database
ISI
SICI code
0009-2673(200009)73:9<2115:TJAERO>2.0.ZU;2-4
Abstract
Catalysts, oligo-L-leucine, for the Julia-Colonna asymmetric epoxidation of chalcone with defined degrees of polymerization were prepared by a stepwis e elongation method. The yield and enantioselectivity in the epoxidation in creased with the degree of polymerization of the catalyst. The presence of an unprotected amine moiety at the N-terminus proved to be essential for hi gh asymmetric induction. The IR characteristic absorption bands (the amide I region) of the catalysts suggested that helical structure in the catalyst is related to asymmetric induction.