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Updated: Feb 22, 2026
Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
Borane-Stabilized Isomeric Dimers of the Phosphaethynolate Anion
Kevin M Szkop1, Andrew R Jupp1, Riccardo Suter2
1Department of Chemistry, University of Toronto, 80 St. George St., Toronto, Ontario, M5S3H6, Canada.
Abstract:
The reactions of the phosphaethynolate anion ([PCO]- ) with a range of boranes were explored. BPh3 and [PCO]- form a dimeric anion featuring P-B bonds and is prone to dissociation at room temperature. The more Lewis acidic borane B(C6 F5 )3 yields a less symmetric dimer of [PCO]- with P-B and P-O bonds. Less sterically demanding HB(C6 F5 )2 and H2 B(C6 F5 ) boranes form a third isomer with [PCO]- featuring both boranes bound to the same phosphorus atom. Despite the unexpected thermodynamic preference for P-coordination, computational data illustrate that electronic and steric features impact the binding modes of the resulting dianionic dimers.
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