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Updated: Jun 5, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
Bis(2,6-dimethyl-pyridinium) tetra-bromido-cobaltate(II)
Abstract:
In the crystal structure of the title compound, (C(7)H(10)N)(2)[CoBr(4)], the [CoBr(4)](2-) anion is connected to two cations through N-H⋯Br and H(2)C-H⋯Br hydrogen bonds to form two-dimensional cation-anion-cation layers normal to the crystallographic b axis. Inter-actions of the π-π type are absent between cations in the stacks [centroid-centroid separation = 5.01 (5) Å]. Significant inter-molecular Br-aryl inter-actions are present in the structure, especially an unusually short Br-ring centroid inter-action of 3.78 (1) Å. The coordination geometry of the anion is approximately tetrahedral and a twofold rotation axis passes through the Co atom.
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