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Updated: Jul 28, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
A stable N-heterocyclic carbene with a diboron backbone
Kelly E Krahulic1, Gary D Enright, Masood Parvez
1Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, T2N 1N4 Canada.
Abstract:
The synthesis of a novel five-membered inorganic ring, a stable N-heterocyclic carbene with a diboron backbone, is reported. A pentacarbonyltungsten complex containing the new carbene is also described. Spectroscopic evidence indicates that the sterically encumbered carbene is a better sigma-donor than classical N-heterocyclic analogues, demonstrating the significant influence of the inorganic backbone on the coordinating properties of the carbon ligand. Crystal structures have been determined for an iminium precursor, the free carbene, and the tungsten complex.
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