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Updated: Feb 28, 2026
14:07
Preparation and Use of Carbonyl-decorated Carbenes in the Activation of White Phosphorus
Published on: October 3, 2014
14.2K
A model for C-F activation by electrophilic phosphonium cations
Ian Mallov1, Timothy C Johnstone, Darcy C Burns
1Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada. dstephan@chem.utoronto.ca.
Chemical Communications (Cambridge, England)
|June 21, 2017
Summary
Researchers synthesized a novel electrophilic phosphonium cation (EPC) salt. This EPC salt exhibits a unique interaction between its trifluoromethyl group and the phosphonium center, offering insights into C-F bond activation mechanisms.
Area of Science:
- Organometallic Chemistry
- Fluorine Chemistry
- Main Group Chemistry
Background:
- Electrophilic phosphonium cations (EPCs) are valuable synthetic intermediates.
- Understanding interactions within EPCs is crucial for developing new chemical transformations.
- Main group C-F bond activation remains a significant challenge in synthetic chemistry.
Purpose of the Study:
- To synthesize and characterize a novel electrophilic phosphonium cation (EPC) salt.
- To investigate the structural and electronic properties of the synthesized EPC.
- To explore the potential for intramolecular interactions influencing C-F bond activation.
Main Methods:
- Oxidation of a phosphine precursor using Xenon difluoride (XeF2).
- Fluoride ion abstraction to form the target phosphonium salt.
- Structural characterization using X-ray crystallography and spectroscopy.
- Computational analysis using Atoms in Molecules (AIM) and Natural Bond Orbital (NBO) methods.
Main Results:
- Successful synthesis of the electrophilic phosphonium cation (EPC) salt [C10H6(CF3)PF(C6F5)2][B(C6F5)4].
- Structural and spectroscopic data indicate an interaction between the CF3 group's fluorine and the phosphonium center.
- AIM and NBO analyses confirm lone pair donation from CF3 fluorine to the P-F sigma* orbital.
Conclusions:
- The synthesized EPC salt demonstrates an unusual intramolecular interaction.
- This interaction provides evidence supporting proposed mechanisms for main group C-F bond activation.
- The findings contribute to the understanding of bonding and reactivity in fluorinated organophosphorus compounds.
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