Investigation of the palladium catalyzed aromatic coupling of pyridine derivatives
2000 (English)In: Journal of Molecular Catalysis A: Chemical, ISSN 1381-1169, Vol. 164, no 1-2, 137-146 p.Article in journal (Refereed) Published
The coupling reaction of 4-methylpyridine to form 4,4 ' -dimethyl-2,2 ' -bipyridine using a carbon-supported palladium catalyst was studied. Whereas previous research indicated that the reaction is catalyzed by palladium(0), we have found evidence that the reaction is catalyzed by palladium(II). Although oxygen can be used as the oxidative agent, the reaction is ultimately Limited by catalyst deactivation. The major source of deactivation is most likely depletion of the palladium(II) oxide. The catalyst is reduced during the reaction and in the case of the oxygen-treated catalyst a small amount of palladium appears to be dissolved. In an investigation of the catalyst using X-ray photoelectron spectroscopy (XPS) and solid state nuclear magnetic resonance (NMR) it was found that deactivation is also caused by poisoning, the poison being either the product and/or the by-product.
Place, publisher, year, edition, pages
2000. Vol. 164, no 1-2, 137-146 p.
palladium, catalysis, aromatic coupling, NMR, XPS, complexes, ligands, oxidation, ruthenium, polymers
IdentifiersURN: urn:nbn:se:kth:diva-20249ISI: 000166078400015OAI: oai:DiVA.org:kth-20249DiVA: diva2:338942
QC 201005252010-08-102010-08-10Bibliographically approved