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Updated: May 26, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
A versatile protocol for the quantitative and smooth conversion of phosphane oxides into synthetically useful
Kai-Oliver Feldmann1, Stephen Schulz, Felix Klotter
1Institut für Anorganische und Analytische Chemie and Graduate School of Chemistry, WWU Münster, Münster, Germany.
Abstract:
A convenient protocol for the smooth conversion of the resistant P-O bond in phosphane oxides into a reactive P-N bond of synthetically useful pyrazolylphosphonium salts is described. A highly charged, oxophilic, phosphorus-centered trication is employed and the reactions are conducted at room temperature with quantitative yields. The resulting pyrazolylphosphonium cations are valuable synthetic intermediates and are used for the synthesis of a variety of organophosphorus compounds. This represents a new approach towards the transformation of the rather inert phosphoryl group under very mild reaction and workup conditions and aims towards alternatives to existing reduction methods for phosphane oxide functionalization.
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