Entropy-controlled asymmetric synthesis. How differential activation entropy is induced in chiral tethered reactions

Citation
T. Sugimura et al., Entropy-controlled asymmetric synthesis. How differential activation entropy is induced in chiral tethered reactions, ORG LETT, 3(1), 2001, pp. 37-40
Citations number
32
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Organic Chemistry/Polymer Science
Journal title
ORGANIC LETTERS
ISSN journal
1523-7060 → ACNP
Volume
3
Issue
1
Year of publication
2001
Pages
37 - 40
Database
ISI
SICI code
1523-7060(20010111)3:1<37:EASHDA>2.0.ZU;2-B
Abstract
[GRAPHICS] Kinetic measurements to determine effective molarities of intramolecular re actions using 2,4-pentanediol and related tethers showed that methyl groups on the tether accelerate the major diastereomeric process but decelerate t he minor process. The efficient promotion of stereocontrol is suggested to be due to chiral perturbation of the reaction rate through the entropy term , The conformation of the encounter complex of the reagent and reactant moi eties was deduced by stereochemical analysis of the intramolecular adducts.