Glucosamine Research Today is a free monthly online journal that collates and summarizes the latest research about Glucosamine, including details on chondroitin sulfate, uses, effects, benefits, arthritis.

Screening of a Modular Sugar-Based Phosphite-Oxazoline Ligand Library in Asymmetric Pd-Catalyzed Heck Reactions.

Mata Y, Pàmies O, Diéguez M

Departament de Química Física i Inorgànica, Universitat Rovira i Virgili. Campus Sescelades, C/Marcel⋅lí Domingo, s/n. 43007 Tarragona, Spain, Fax: (+34) 977-559-563.

We have synthesised a library of phosphite-oxazoline ligands derived from readily available D-glucosamine. These ligands have been successfully screened in the palladium-catalysed Heck reaction of several substrates with high regio- (up to 99 %) and enantioselectivities (ee's up to 99 %) as well as with improved activities under standard thermal conditions. The results indicate that the catalytic performance is highly affected by the oxazoline and biarylphosphite substituents and the axial chirality of the biaryl moiety of the ligand. The Heck reactions were also performed under microwave irradiation conditions, allowing a considerably shorter reaction time (full conversion in minutes) maintaining the excellent regio- and enantioselectivities.

Published 9 April 2007 in Chemistry, 13(12): 3296-3304.
Full-text of this article is available online (may require subscription).

© 2004-2008 Glucosamine Research Today. All Rights Reserved.