Trimethylphosphite

Trimethyl phosphite

Names
IUPAC name Trimethyl phosphite
Other names Trimethoxyphosphine
Identifiers
CAS Number	121-45-9 Y
3D model (Jmol)	Interactive image
ChemSpider	8159 Y
ECHA InfoCard	100.004.065
PubChem CID	8472
InChI InChI=1S/C3H9O3P/c1-4-7(5-2)6-3/h1-3H3 Y Key: CYTQBVOFDCPGCX-UHFFFAOYSA-N Y InChI=1/C3H9O3P/c1-4-7(5-2)6-3/h1-3H3 Key: CYTQBVOFDCPGCX-UHFFFAOYAO
SMILES O(P(OC)OC)C
Properties
Chemical formula	C3H9O3P
Molar mass	124.08
Appearance	colorless liquid
Odor	distinctive, pungent
Density	1.052
Melting point	−78 °C (−108 °F; 195 K)
Boiling point	111 °C (232 °F; 384 K)
Solubility in water	reacts
Vapor pressure	24 mmHg (25°C)
Hazards
Flash point	28 °C; 82 °F; 301 K
US health exposure limits (NIOSH):
PEL (Permissible)	none
REL (Recommended)	TWA 2 ppm (10 mg/m3)
IDLH (Immediate danger)	N.D.
Related compounds
Related compounds	Dimethyl methylphosphonate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Trimethylphosphite is an organophosphorus compound with the formula P(OCH₃)₃, often abbreviated P(OMe)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 methoxide groups.

Although commercially available, trimethylphosphite is prepared from phosphorus trichloride:

It is susceptible to oxidation to trimethyl phosphate.

As a ligand, trimethylphosphite has a smaller cone angle and better acceptor properties relative to trimethylphosphine. A representative derivative is the colorless, tetrahedral complex Ni(P(OMe)₃)₄ (m.p. 108 °C). The tridentate ligand called the Klaui ligand is derived from trimethylphosphite. The formation of this ligand illustrates the susceptibility of trimethylphosphite (and metal complexes thereof) to the Arbuzov reaction.

Trimethylphosphite is also used as a mild desulfurization reagent in organic synthesis, for example in the preparation of derivatives of tetrathiafulvalene.