Density 969 kg/m³ Formula C6H15O3P Main hazards toxic Pubchem 31215 | Boiling point 156 °C Molar mass 166.16 g/mol Appearance colorless liquid | |
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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. Its 31P NMR spectrum features a signal at around +139 ppm vs phosphoric acid standard.
Triethylphosphite is prepared by treating phosphorus trichloride with ethanol in the presence of a base, typically a tertiary amine:
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).