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Updated: Jul 5, 2025
08:46
Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
7.8K
Exploring Electrophilic Hydrophosphination via Metal Phosphenium Intermediates
Roman G Belli1, Vanessa Muir1, Nicholas B Dyck1
1Department of Chemistry, University of Victoria, P.O. Box 1700, STN CSC, Victoria, British Columbia, Canada, V8W 2Y2.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|January 19, 2024
Summary
This study demonstrates a new metal-catalyzed electrophilic hydrophosphination mechanism using molybdenum phosphenium complexes. These complexes enable P-H addition to unsaturated substrates, offering a novel synthetic pathway.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Phosphorus Chemistry
Background:
- Metal-catalyzed hydrophosphination is an emerging area in synthetic chemistry.
- Phosphenium complexes offer unique reactivity profiles for P-H bond functionalization.
Purpose of the Study:
- To investigate the electrophilic addition and P-H hydride transfer capabilities of Mo(0) phosphenium complexes.
- To provide proof of concept for a novel metal-catalyzed electrophilic hydrophosphination mechanism.
Main Methods:
- Synthesis and characterization of Mo(0) phosphenium complexes with secondary phosphine ligands.
- Stoichiometric reactions with various unsaturated substrates (alkenes, ketones).
- Mechanistic investigations including kinetic and computational analyses.
Main Results:
- Two Mo(0) phosphenium complexes were synthesized and studied.
- The more Lewis acidic complex effectively hydrophosphinates specific substrates, while the less acidic complex shows broader substrate scope.
- Mechanistic studies probed the electrophilic pathway and hydride transfer.
Conclusions:
- The study provides stoichiometric evidence for a new metal-catalyzed electrophilic hydrophosphination mechanism.
- Different Lewis acidity of phosphenium complexes influences substrate scope and reactivity.
- Further research is needed to overcome challenges for catalytic applications.
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