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Updated: May 12, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
On the synthesis and reactivity of highly labile pseudohalogen phosphenium ions
Christian Hering1, Axel Schulz, Alexander Villinger
1Institut für Chemie, Abteilung Anorganische Chemie, Universität Rostock, Albert-Einstein-Strasse 3a, 18059 Rostock, Germany.
Abstract:
The synthesis and characterization of salts bearing highly labile pseudohalogen-substituted aminophosphenium cations of the type [(Me3Si)2NPX][GaCl4] (X = NCO, NCS, O(SiMe3)) and their respective reactivity toward Lewis bases (4-dimethylaminopyridine, dmap) and dienes (2,3-dimethyl-1,3-butadiene, dmb; 1,3-cyclo-hexadiene, chd) are described. As π-acidic species, aminophosphenium cations react with dmap at low temperatures to yield adduct salts of the type [(Me3Si)2NP(dmap)X][GaCl4] (X = Cl, N3, NCO) which were fully characterized. In the reaction with dienes at -50 °C, salts bearing phospholenium cations were obtained that could be structurally characterized. The crystal structures of novel 7-phosphanorbornenium cations of the type [(Me3Si)2NP(C6H8)X][GaCl4] (X = Cl, N3, NCO) are reported. All compounds were further investigated by means of density functional theory, and the bonding situation was accessed by Natural Bond Orbital (NBO) analysis.
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