Related Experiment Video
Updated: May 16, 2026
14:07
Preparation and Use of Carbonyl-decorated Carbenes in the Activation of White Phosphorus
Published on: October 3, 2014
Visible-Light Unlocked Carbene Insertion and Radical Release in a Structurally Constrained Pincer Phosphorus Compound
Avisek Ghosh1, Aqeel A Hussein2, Jing Liu3,4
1CNRS/Université De Toulouse, Laboratoire Hétérochimie Fondamentale Et Appliquée (LHFA, UMR5069), Toulouse, France.
Angewandte Chemie (International Ed. in English)
|May 14, 2026
Summary
Geometrically constrained phosphines, when excited by visible light, mimic transition metal reactivity. This study reveals a novel light-driven cycle for phosphines, enabling new catalytic pathways.
Area of Science:
- Organometallic Chemistry
- Photochemistry
- Main-group Chemistry
Background:
- Geometrically constrained phosphines are explored as alternatives to transition metals in catalysis.
- Understanding the photochemical behavior of these constrained phosphines is key to unlocking novel reactivity.
Purpose of the Study:
- To investigate the transition-metal-like reactivity of a geometrically constrained ONO-pincer phosphine under visible-light excitation.
- To establish a light-driven reactivity loop involving phosphines and phosphoranes.
Main Methods:
- Visible-light photochemistry
- Time-resolved Electron Paramagnetic Resonance (EPR) spectroscopy
- Density Functional Theory (DFT) calculations
Main Results:
- Visible-light excitation of an ONO-pincer phosphine generates α-siloxy carbenes, leading to P─C bond formation and bicyclic phosphines.
- These intermediates form stable phosphoranes, which upon further irradiation, undergo P─C bond homolysis, releasing radicals and regenerating the phosphine.
- Geometric constraint was found crucial for carbene insertion and P─C bond homolysis pathways.
Conclusions:
- A rare light-driven phosphine → phosphorane → phosphine (P(III) → P(V) → P(III)) reactivity cycle was established.
- Structural constraints enable main-group elements to perform catalytic steps analogous to transition metals.
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