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Updated: Aug 22, 2025

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
1,1'-Methyl-enebis{4-[(E)-2-(pyridin-4-yl)ethen-yl]pyridinium} dibromide dihydrate
Henry C Neal1, Volodymyr V Nesterov2, Bradley W Smucker1
1Austin College, 900 N Grand, Sherman, TX 75090, USA.
Abstract:
The chevron-shaped cations of the title hydrated salt, C25H22N4 2+·2Br-·2H2O, are arranged in back-to-back alternating directions to form a zigzag ribbon propagating along the [010] direction. Inter-molecular inter-actions comprising these ribbons are π-π inter-actions between the pyridinium and adjacent pyridyl rings, as well as O-H⋯O hydrogen bonding between water molecules and two adjacent pyridyl N atoms. Half of the cation is generated by the mirror plane. The water O atoms, the central C atom and one Br atom are located on this mirror plane while the other Br atom is on a twofold screw axis.
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