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Updated: Jun 1, 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-diamino-3,5-dibromo-pyridinium) hexa-bromidostannate(IV)
Abstract:
The asymmetric unit of the title compound, (C(5)H(6)Br(2)N(3))(2)[SnBr(6)], contains one cation and one half-anion in which the Sn atom is located on a crystallographic centre of inversion and is in a quasi-octa-hedral geometry. The crystal structure is assembled via hydrogen-bonding inter-actions of two kinds, N(pyridine/amine)-H⋯Br-Sn, along with C-Br⋯Br-Sn interactions [3.4925 (19) Å]. The cations are involved in π-π stacking, which adds an extra supra-molecularity as it presents a strong case of offset-face-to-face motifs [centroid-centroid distance = 3.577 (3) Å]. The inter-molecular hydrogen bonds, short Br⋯Br inter-actions and π-π stacking result in the formation of a three-dimensional supra-molecular architecture.
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