Radical intermediates in chloroform reactions over triphenylphosphine-protected Au nanoparticles

Conte, Marco, Wilson, Karen and Chechik, Victor 2009. Radical intermediates in chloroform reactions over triphenylphosphine-protected Au nanoparticles. Organic and Biomolecular Chemistry 7 (7) , pp. 1361-1367. 10.1039/b819627c

Full text not available from this repository.

Abstract

Reactions of chloroform over triphenylphosphine-protected Au nanoparticles have been studied using electron paramagnetic resonance (EPR) spectroscopy and a spin trapping technique. Two competing reactions, abstraction of hydrogen and halogen atoms, were identified. The hydrogen abstraction reaction showed an inverse kinetic isotope effect. Treatment of nanoparticles with oxidizing or reducing reagents made it possible to tune the selectivity of radical formation from halogen to hydrogen (deuterium) abstraction. Treatment with PbO2 promoted the deuterium abstraction reaction followed by the loss of nanoparticle activity, whereas treatment with NaBH4 regenerated the nanoparticle activity towards Cl atom abstraction. X-ray photoelectron spectroscopy showed an increased Au:P ratio upon treatment with oxidizing reagents. This is likely due to the oxidation of some phosphine ligands to phosphine oxides which then desorb from the nanoparticle surface.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Chemistry Cardiff Catalysis Institute (CCI)
Subjects:	Q Science > QD Chemistry
Publisher:	Royal Society of Chemistry
ISSN:	1477-0520
Last Modified:	19 Mar 2016 22:41
URI:	https://orca.cardiff.ac.uk/id/eprint/23956

Citation Data

Cited 15 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item