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Triethyl phosphite

Triethyl phosphite

IUPAC name	Triethyl phosphite
Other names	Triethoxyphosphine
Identifiers
CAS number	122-52-1
PubChem	24900347
Properties
Molecular formula	C₆H₁₅O₃P
Molar mass	166.16
Appearance	colorless liquid
Density	0.969
Melting point	-70 °C, 203 K, -94 °F
Boiling point	57–58°/16 mm °C
Solubility in water	organic solvents
Hazards
Main hazards	toxic
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Triethylphosphite is an organophosphorus compound with the formula P(OCH₂CH₃)₃, often abbreviated P(OEt)₃. This colorless liquid is used as a ligand in organometallic chemistry and as a reagent in organic synthesis. The molecule features a pyramidal phosphorus(III) center bound to three ethoxide groups.

Additional recommended knowledge

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Triethylphosphite is prepared by treating phosphorus trichloride with ethanol in the presence of a base, typically a tertiary amine:^[1]

PCl₃ + 3 EtOH + 3 R₃N → P(OEt)₃ + 3 R₃NH⁺Cl^-

Of the many related compounds can be prepared similarly, triisopropyl phosphite is an example (b.p. 43.5 °C/1.0 mm; CAS# 116-17-6).

As a ligand

In coordination chemistry and homogeneous catalysis]], triethylphosphite finds use as a soft ligand. Its complexes are generally lipophilic and feature metals in low oxidation states. Examples include the colorless complexes FeH₂(P(OEt)₃)₄ and Ni(P(OEt)₃)₄ (m.p. 187 °C).^[2]

References

^ A. H. Ford-Moore and B. J. Perry (1963). "Triethyl Phosphite". Org. Synth.; Coll. Vol. 4: 955.
^ Ittel, Steven D. (1990). "Complexes of Nickel(0)". Inorganic Syntheses 28: 98-104. doi:10.1002/9780470132593.ch26.