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Updated: Oct 26, 2025

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
Allenic phosphonium borate zwitterions via a phosphonium allenylidene intermediate
Lucas C Torres1, Roman Dobrovetsky, Christopher B Caputo
1Department of Chemistry, York University, Keele Street 4700, Toronto, Ontario M3J1P3, Canada. caputo@yorku.ca.
Abstract:
We describe the synthesis of alkynyl phosphanes of the type R2P-C[triple bond, length as m-dash]C-C(OCH3)Ph2 (R = Ph, Cy) and investigate their transformation to geminally substituted phosphonium borato-allene zwitterions upon their reaction with B(C6F5)3. The mechanism for this transformation was studied experimentally and by density functional theory computations (DFT), suggesting the intermediacy of an unsaturated 3-coordinate phosphonium electrophile akin to a methylene phosphonium cation.
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