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Updated: May 27, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
O,O'-2-Iodo-1,3-phenyl-ene bis-(diphenyl-phosphinothio-ate)
Abstract:
The title compound, C(30)H(23)IO(2)P(2)S(2), was synthesized by the reaction of 2-iodo-benzene-1,3-diol, chloro-diphenyl-phosphine, Et(3)N and sulfur. The P=S bonds project to opposite sides of the central aromatic ring. The O-P-S and C-P-S bond angles are significantly larger than the O-P-C and C-P-C bond angles, indicating significant distortion of the tetra-hedral geometries of the P atoms. The P=S bond lengths of 1.9311 (13) and 1.9302 (12) Å in the title compound are shorter than that found in Ph(3)P=S [1.950 (3) Å] because the replacement of one C atom attached the P atom by an O atom increases the effective electronegativity of the P atom.
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