Trioctylphosphine oxide

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Trioctylphosphine oxide
Trioctylphosphine oxide.png
Preferred IUPAC name
Other names
Tri-n-octylphosphine oxide
3D model (JSmol)
ECHA InfoCard 100.001.020 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 201-121-3
MeSH Trioctyl+phosphine+oxide
PubChem CID
RTECS number
  • SZ1662500
UN number 3077
  • InChI=1S/C24H51OP/c1-4-7-10-13-16-19-22-26(25,23-20-17-14-11-8-5-2)24-21-18-15-12-9-6-3/h4-24H2,1-3H3 Yes check.svgY
  • InChI=1/C24H51OP/c1-4-7-10-13-16-19-22-26(25,23-20-17-14-11-8-5-2)24-21-18-15-12-9-6-3/h4-24H2,1-3H3
Molar mass 386.645 g·mol−1
AppearanceWhite, opaque crystals
Melting point 50 to 54 °C (122 to 129 °F; 323 to 327 K)
Boiling point 411.2 °C (772.2 °F; 684.3 K)at 760 mmHg [1]
Hazards [2]
GHS pictograms GHS-pictogram-acid.svg
GHS Signal word Danger
H315, H318
P264, P280, P302+P352, P305+P351+P338, P310, P332+P313, P362
NFPA 704 (fire diamond)
Flash point 110 °C (230 °F; 383 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Trioctylphosphine oxide (TOPO) is an organophosphorus compound with the formula OP(C8H17)3. Frequently referred to as TOPO, this compound is used as an extraction or stabilizing agent. It is an air-stable white solid at room temperature.

Preparation and use

TOPO is usually prepared by oxidation of trioctylphosphine, which in turn is produced by alkylation of phosphorus trichloride.

The main use of TOPO is in solvent extraction of metals, especially uranium. The high lipophilicity and high polarity are properties key to this application. Its high polarity, which results from the dipolar phosphorus-oxygen bond, allows this compound to bind to metal ions. The octyl groups confer solubility in low polarity solvents such as kerosene. [3]

In the research laboratory, both trioctylphosphine and TOPO are frequently useful as a capping ligand for the production of quantum dots such as those consisting of CdSe. In these cases, TOPO serves as solvent for the synthesis and solubilizes the growing nanoparticles. TOPO-coated quantum dots are typically soluble in chloroform, toluene, and (to a lesser extent) hexane. These quantum dots are also used in biological applications as part of the protective barrier to prevent degradation as it travels through the harsh climate of the body.

Related Research Articles

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Solvation Association of molecules of a solvent with molecules or ions of a solute

Solvation describes the interaction of solvent with dissolved molecules. Both ionized and uncharged molecules interact strongly with solvent, and the strength and nature of this interaction influence many properties of the solute, including solubility, reactivity, and color, as well as influencing the properties of the solvent such as the viscosity and density. In the process of solvation, ions are surrounded by a concentric shell of solvent. Solvation is the process of reorganizing solvent and solute molecules into solvation complexes. Solvation involves bond formation, hydrogen bonding, and van der Waals forces. Solvation of a solute by water is called hydration.

Solubility Capacity of a substance to dissolve in a solvent in a homogeneous way

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Flux (metallurgy)

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Acetylide refers to chemical compounds with the chemical formulas MC≡CH and MC≡CM, where M is a metal. The term is used loosely and can refer to substituted acetylides having the general structure RC≡CM. Acetylides are reagents in organic synthesis. The calcium acetylide commonly called calcium carbide is a major compound of commerce.

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Hexafluorophosphate is an anion with chemical formula of PF
. It is an octahedral species that imparts no color to its salts. PF
is isoelectronic with sulfur hexafluoride, SF6, and the hexafluorosilicate dianion, SiF2−
, and fluoroantimonate SbF
. Being poorly nucleophilic, hexafluorophosphate is classified as a non-coordinating anion.

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Superheated water

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  1. Nakhutin, I. E. (1971). Zhurnal Obshchei Khimii. 41 (5): 940–943.Missing or empty |title= (help)
  2. "C&L Inventory".
  3. Watson, E. K.; Rickelton, W. A. "A review of the industrial and recent potential applications of trioctylphosphine oxide" Solvent Extraction and Ion Exchange 1992, volume 10, pp. 879-89. doi : 10.1080/07366299208918141