Chinese Japanese Germany Korea

Trimethyl phosphite

Trimethyl phosphite
Trimethyl phosphite structure
Chemical Name:
Trimethyl phosphite
P(OMe)3;P(OCH3)3;AURORA KA-1230;Trimethylfosfit;Trimethoxyfosfin;METHYL PHOSPHITE;TrimethyPhosphite;Trimethylphosphit ;Trimethoxyphosphine;TRIMETHYLPHOSPHIT S
Molecular Formula:
Formula Weight:
MOL File:

Trimethyl phosphite Properties

Melting point:
−78 °C(lit.)
Boiling point:
111-112 °C(lit.)
1.052 g/mL at 25 °C(lit.)
vapor density 
4.3 (vs air)
vapor pressure 
17 mm Hg ( 20 °C)
refractive index 
n20/D 1.408(lit.)
Flash point:
82 °F
storage temp. 
Specific Gravity
explosive limit
Water Solubility 
Hydrolyzes with water.
Air & Moisture Sensitive
Exposure limits
TLV-TWA 10 mg/m3 (2 ppm) (ACGIH).
CAS DataBase Reference
121-45-9(CAS DataBase Reference)
NIST Chemistry Reference
Phosphorous acid, trimethyl ester(121-45-9)
EPA Substance Registry System
Trimethyl phosphite (121-45-9)
  • Risk and Safety Statements
Signal word  Danger
Hazard statements  H226-H302-H315-H317-H318-H335-H341-H351-H313-H319-H361
Precautionary statements  P201-P303+P361+P353-P405-P501a-P210-P280-P301+P312+P330-P305+P351+P338+P310-P370+P378-P261-P305+P351+P338
Hazard Codes  Xn,T,F,Xi
Risk Statements  10-22-36/37/38-41-37/38-65-48/23/24/25-11-46-45-67-66-36
Safety Statements  26-39-62-45-16-53
RIDADR  UN 2329 3/PG 3
WGK Germany  1
RTECS  TH1400000
Autoignition Temperature 250 °C
HSCode  2920 23 00
HazardClass  3
PackingGroup  III
Toxicity LD50 orally in Rabbit: 1600 mg/kg LD50 dermal Rabbit 2600 mg/kg
NFPA 704

Trimethyl phosphite price More Price(18)

Manufacturer Product number Product description CAS number Packaging Price Updated Buy
Sigma-Aldrich 240907 Trimethyl phosphite ≥99% 121-45-9 25g $33.1 2019-12-02 Buy
Sigma-Aldrich 240907 Trimethyl phosphite ≥99% 121-45-9 100g $90.7 2019-12-02 Buy
Alfa Aesar 030132 Trimethyl phosphite 97% 121-45-9 500g $128 2019-12-02 Buy
Alfa Aesar 030132 Trimethyl phosphite, 97% 121-45-9 100g $34 2019-12-02 Buy
Strem Chemicals 15-6550 Trimethylphosphite, 97% 121-45-9 1kg $156 2019-12-02 Buy

Trimethyl phosphite Chemical Properties,Uses,Production

Chemical Properties

Trimethyl phosphite is a colorless liquid. Distinctive pungent, pyridine-like odor. The Odor Threshold is 0.0001 ppm.


Chemical intermediate, especially for insecticides.


Trimethyl phosphite is used in the manufacture of pesticides and fire retardants..

Production Methods

Produced via a reaction between phosphorus trichloride and methanol in the presence of a tertiary amine catalyst such as diethylaniline.

General Description

A clear colorless liquid with a strong foul odor. Flash point 99°F. Denser than water and insoluble in waterwater; soluble in hexane, benzene, acetone, alcohol, ether, carbon tetrachloride, and kerosene.. Vapors heavier than air. Used to make other chemicals.

Air & Water Reactions

Highly flammable. Insoluble in water and denser than water. Slowly reacts with water to form phosphoric acid and corresponding organic alcohol.

Reactivity Profile

As soon as Trimethyl phosphite contacted a small amount of magnesium perchlorate in a flask, there was a flash and an explosion that shattered the flask (Allison 1968).

Health Hazard

Symptoms of exposure may include burning sensation, coughing, wheezing, laryngitis, shortness of breath, headache, nausea, and vomiting.

Health Hazard

Trimethyl phosphite is a skin, eye, and mucous membrane irritant with low subacute inhalation toxicity. Its irritating action on rabbits’ skin was moderate to severe. The pure liquid instilled into the eyes can cause severe irritation and swelling, which can last for a few days. Chronic exposure to 300–600 ppm concentration in air produced lung inflammation and cataracts in mice. There was no acute inhalation toxicity observed in test animals. The oral and dermal toxicities were low.
LD50 value, oral (rats): 1600 mg/kg
Teratogenic effects showing gross abnormalities were observed in newborn rats when pregnant rats were dosed with high concentrations of trimethyl phosphite.
The odor threshold for this compound was determined to be 0.0001 ppm (ACGIH 1986). The odor is irritating and pungent at high concentrations..

Fire Hazard

Special Hazards of Combustion Products: Toxic fumes of PO x

Safety Profile

Moderately toxic by ingestion and skin contact. An experimental teratogen. A severe skin and eye irritant. Flammable liquid when exposed to heat, flame, or oxidizers. To fight fire, use water, foam, fog, CO2. Violent explosive reaction on contact with magnesium perchlorate or trimethyl platinum(IV) azide tetramer. When heated to decomposition it emits toxic fumes of POx. An intermediate in the production of pesticides, fire retardants, and organic phosphorus additives. See also ESTERS.

Potential Exposure

Trimethyl phosphite is a flame retardant, and used as an intermediate in the manufacture of a number of pesticides, and organophosphorus additives.


UN2329 Trimethyl phosphite, Hazard Class: 3; Labels: 3-Flammable liquid.

Purification Methods

Treat the phosphite with Na (to remove water and any dialkyl phosphonate), then decant and distil it with protection against moisture. It has also been treated with sodium wire for 24hours, then distilled in an inert atmosphere onto activated molecular sieves [Connor et al. J Chem Soc, Dalton Trans 511 1986]. It can be fractionally distilled using a spinning band column at high reflux ratio. It is a colourless liquid which is slowly hydrolysed by H2O. [Gillis et al. J Am Chem Soc 80 2999 1958, NMR: Callis et al. J Am Chem Soc 79 2719 1957, Kosolapoff Organophosphorus Compounds, Wiley p 203 1950, Beilstein 1 IV 1256.]


Vaor May form explosive mixture with air. Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Violent reaction with magnesium perchlorate. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides. Reacts (hydrolyzes) with water. Incompatible with air, moisture.

Waste Disposal

Trimethyl phosphite may be burned in a chemical incinerator equipped with an afterburner and scrubber.

Trimethyl phosphite Preparation Products And Raw materials

Raw materials

Preparation Products

Trimethyl phosphite Suppliers

Global( 149)Suppliers
Supplier Tel Fax Email Country ProdList Advantage
Mainchem Co., Ltd.
+86-0592-6210733 CHINA 32447 55
career henan chemical co
+86-371-86658258 CHINA 29996 58
+86 18953170293
+86 0531-67809011 CHINA 2995 58
Chemwill Asia Co.,Ltd.
86-21-51861608;;; CHINA 23981 58
Hubei Jusheng Technology Co.,Ltd.
027-59599243 CHINA 28236 58
Hubei xin bonus chemical co. LTD
027-59338440 CHINA 23049 58
Chongqing Chemdad Co., Ltd
+86-13650506873 CHINA 35440 58
Henan tianfu chemical co. LTD
0371-55170695 CHINA 20538 58
Meryer (Shanghai) Chemical Technology Co., Ltd. +86-(0)21-61259100(Shanghai) +86-(0)755-86170099(ShenZhen) +86-(0)10-62670440(Beijing)
+86-(0)21-61259102(Shanghai) +86-(0)755-86170066(ShenZhen) +86-(0)10-88580358(Beijing) China 40269 62
Alfa Aesar 400-610-6006
021-67582001/03/05 China 30163 84

View Lastest Price from Trimethyl phosphite manufacturers

Image Release date Product Price Min. Order Purity Supply Ability Manufacturer
2019-07-02 Trimethyl phosphite
US $1.00 / KG 1KG 99 25kg career henan chemical co

Trimethyl phosphite Spectrum

121-45-9(Trimethyl phosphite)Related Search:

Copyright 2017 © ChemicalBook. All rights reserved