Related Experiment Video
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
2,2',7,7'-Tetra-bromo-9,9'-spiro-bifluorene toluene hemisolvate
Abstract:
There are two independent mol-ecules and one toluene solvent mol-ecule in the asymmetric unit of the title compound, C(25)H(12)Br(4)·0.5C(7)H(8). The dihedral angles between the fluorene ring systems are 85.30 (6) and 84.95 (6)° in the two mol-ecules. The disortions in angles from the ideal sp(3)-hybridization geometry around the tetra-hedral C atoms are due to the strain imposed by the central five-membered ring and steric effects.
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