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Updated: May 22, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
[P9]+ [Al(OR(F))4)]-, the salt of a homopolyatomic phosphorus cation
Tobias Köchner1, Tobias A Engesser, Harald Scherer
1Institut für Anorganische und Analytische Chemie, Freiburger Materialforschungszentrum (FMF), Albert-Ludwigs-Universität Freiburg, Germany.
Abstract:
Positive at last: The first condensed-phase homopolyatomic phosphorus cation [P(9)](+) was prepared using a combination of the oxidant [NO](+) and weakly coordinating anion, [Al{OC(CF(3))(3)}(4)](-). [P(9)](+) consists of two P(5) cages linked by a phosphonium atom to give a D(2d)-symmetric Zintl cluster. NMR (see picture), Raman, and IR spectroscopy, mass spectrometry, and quantum-chemical calculations confirmed the structure.
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