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Updated: May 12, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
New chiral zwitterionic phosphorus heterocycles: synthesis, structure, properties and application as chiral solvating
Andrey E Sheshenev1, Ekaterina V Boltukhina, Anastasiya A Grishina
1Department of Chemistry, Imperial College London, Exhibition Road, SW7 2AZ London, UK.
Abstract:
A family of new chiral zwitterionic phosphorus-containing heterocycles (zPHC) have been derived from methylene-bridged bis(imidazolines). These structures were unambiguously determined, including single-crystal XRD analysis for two compounds. The stability, acid/base and electronic properties of these dipolar phosphorus heterocycles were subsequently investigated. zPHCs can be successfully employed as a new class of chiral solvating agents for the enantiodifferentiation of chiral carboxylic and sulfonic acids by NMR spectroscopy. The stoichiometry and binding constants for the donor-acceptor complexes formed were established by NMR titration methods.
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