The UvA-LINKER will give you a range of other options to find the full text of a publication (including a direct link to the full-text if it is located on another database on the internet).
De UvA-LINKER biedt mogelijkheden om een publicatie elders te vinden (inclusief een directe link naar de publicatie online als deze beschikbaar is in een database op het internet).

Zoekresultaten

Zoekopdracht: faculteit: "FNWI" en publicatiejaar: "2004"

AuteursG. Rothenberg, S.C. Cruz, G.P.F. van Strijdonck, H.C.J. Hoefsloot
TitelDetailed mechanistic studies using in situ spectroscopic analysis: A look at little-known regions of the heck reaction
TijdschriftAdvanced Synthesis & Catalysis
Jaargang346
Jaar2004
Nummer4
Pagina's467-473
ISSN16154150
FaculteitFaculteit der Natuurwetenschappen, Wiskunde en Informatica
Instituut/afd.FNWI: Van 't Hoff Institute for Molecular Sciences (HIMS)
FNWI: Swammerdam Institute for Life Sciences (SILS)
Trefwoordencatalyst deactivation; cross coupling; homogeneous catalysis; kinetic analysis; palladium; spectroscopy
Basisclassificatie35.25 analytical chemistry: spectrochemical analysis
SamenvattingThe mechanism of the Heck reaction using palladium complexes with large phosphoramidite ligands is investigated. The catalyst precursor is an inactive dimer that equilibrates with the active monomeric species. A series of kinetic models is introduced and compared with concentration profiles obtained from FT-NIR spectroscopy. First, an analytical solution of the differential equations for a simplified mechanism is considered. This fits well at low conversions but deviates at higher conversions with increasing deactivation. Formation of palladium clusters and palladium black is then included, with the simplification that all the deactivation processes are represented by a single first-order process. This results in a five-step mechanism that describes the dimer-monomer equilibrium, the Pd(II)/Pd(0) catalytic cycle, and the catalyst deactivation process. The model can be used to monitor the transient concentrations of the virtual Pd(0), Pd(II), and dimer catalyst species, and helps to explain the effects of water. The high resolution of the measurements and low error levels of the models render this approach a powerful tool for mechanistic studies in homogeneous catalysis.
Soort documentArtikel
Document finderUvA-Linker