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Updated: Jul 15, 2025
Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
An ab initio study on the stability of isolated phosphaalkene synthons
Adrianna Cyraniak1, Sylwia Freza1, Piotr Skurski1,2
1Laboratory of Quantum Chemistry, Department of Theoretical Chemistry, Faculty of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland. piotr.skurski@ug.edu.pl.
Abstract:
Using ab initio methods and flexible basis sets, we examined the electronic, geometric, and thermodynamic stabilities of selected phosphaalkene synthons matching the (PCR2)- formula (R = H, CH3, C6H5, C6F5, and Mes). All isolated synthons considered were found to be electronically stable and susceptible to neither fragmentation nor isomerization processes. The structures corresponding to the most stable isomers of the studied phosphaalkene synthons contain a PC double-bond (whose presence was confirmed by natural bond orbital occupancies of σ(P-C) and π(P-C) approaching 2 electrons) and two R substituents connected to the carbon atom in either (PCR2)- (for R = H, CH3, C6H5, and Mes) or (PCF-R-R)- (for R = C6F5) manner. Vertical electron detachment energies (spanning the 0.924-3.118 eV range) characterizing the phosphaalkene synthons were predicted and discussed.
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