Related Experiment Video
Updated: Mar 28, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
Pyridinium-phosphonium dications: highly electrophilic phosphorus-based Lewis acid catalysts
Julia M Bayne1, Michael H Holthausen, Douglas W Stephan
1Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada M5S 3H6. dstephan@chem.utoronto.ca.
Abstract:
Using commercially available 2-pyridyldiphenylphosphine (o-NC5H4)PPh2, a family of electrophilic phosphonium cations [(o-NC5H4)PFPh2](+) (2) and dications [(o-MeNC5H4)PRPh2](2+) (R = F (4); Me (5)) were prepared. The Lewis acidity of these pyridinium-phosphonium dications was probed in Friedel-Crafts dimerization, hydrodefluorination, hydrosilylation, dehydrocoupling and hydrodeoxygenation reactions. The influence of the counterion on the catalytic activity of the electrophilic phosphonium cations is also discussed.
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