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Updated: May 9, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
The 2-phosphaethynolate anion: a convenient synthesis and [2+2] cycloaddition chemistry
Andrew R Jupp1, Jose M Goicoechea
1Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA (UK) http://research.chem.ox.ac.uk/jose-goicoechea.aspx.
Researchers synthesized a novel phosphaethynolate anion from the heptaphosphide trianion. This anion then reacted with diphenylketene and a carbodiimide to form unique four-membered phosphorus-containing rings.
Area of Science:
- Inorganic Chemistry
- Organophosphorus Chemistry
- Synthetic Chemistry
Background:
- The heptaphosphide trianion (P7(3-)) is a unique inorganic cluster with rich reactivity.
- Exploring new synthetic routes and reactive intermediates is crucial for advancing phosphorus chemistry.
Purpose of the Study:
- To directly carbonylate the heptaphosphide trianion (P7(3-)) to form a novel phosphaethynolate anion.
- To investigate the reactivity of the synthesized phosphaethynolate anion in cycloaddition reactions.
Main Methods:
- Direct carbonylation of heptaphosphide trianion solutions.
- [2+2] cycloaddition reactions using diphenylketene and bis(2,6-diisopropylphenyl)carbodiimide.
Main Results:
- Successful synthesis of the phosphaethynolate anion in moderate yields.
- Formation of anionic four-membered heterocycles, P[C(O)]2C(C6H5)2(-) and PC(O)(CNDipp)NDipp(-), via [2+2] cycloaddition.
Conclusions:
- The phosphaethynolate anion is a versatile building block for constructing novel phosphorus heterocycles.
- This study expands the synthetic utility of the heptaphosphide core in organophosphorus chemistry.
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