Trimethyl phosphite

  • Methyl phosphite
  • Trimethoxyphosphine
  • Trimethyl ester of phosphorous acid
Formula
C3H9O3P
Structure
Description
A clear colorless liquid with a strong foul odor.
Uses
Starting material for vinyl phosphate synth as chemical int, in organic synthesis.

Registry Numbers and Inventories.
CAS
121-45-9
EC (EINECS/ELINCS)
204-471-5
RTECS
TH1400000
RTECS class
Reproductive Effector; Primary Irritant
UN (DOT)
2329
Beilstein/Gmelin
956570
Beilstein Reference
4-01-00-01256
Swiss Giftliste 1
G-3017
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C3H9O3P
Formula mass
124.09
Melting point, °C
-77.8
Boiling point, °C
111
Vapor pressure, mmHg
28 (25 C)
Vapor density (air=1)
4.3
Odor Threshold Odor threshold 0.1 ppb
Density
1.042 g/cm3 (20 C)
Solubility in water
Very soluble
Surface tension
26.52 g/s2 (20 C)
Refractive index
1.4095 (20 C)
Partition coefficient, pKow
-0.93
Heat of vaporization
40.6 kJ/mol

Hazards and Protection.
Storage
Keep away from heat, sparks, and flame. Keep away from sources of ignition. Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances. Flammables-area.
Handling
Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Ground and bond containers when transferring material. Use spark-proof tools and explosion proof equipment. Avoid contact with eyes, skin, and clothing. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Keep container tightly closed. Avoid contact with heat, sparks and flame. Avoid ingestion and inhalation. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators
A respiratory protection program that meets OSHA's 29 CFR 1910.134 and ANSI Z88.2 requirements or European Standard EN 149 must be followed whenever workplace conditions warrant a respirator's use.
Small spills/leaks
Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container. Avoid runoff into storm sewers and ditches which lead to waterways. Clean up spills immediately, using the appropriate protective equipment. Remove all sources of ignition. Use a spark-proof tool. Provide ventilation. A vapor suppressing foam may be used to reduce vapors.
Stability
Stable under normal temperatures and pressures.
Incompatibilities
Oxidizing agents.
Decomposition
Carbon monoxide, oxides of phosphorus, irritating and toxic fumes and gases, carbon dioxide.

Fire.
Flash Point,°C
27
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Will burn if involved in a fire. Use water spray to keep fire-exposed containers cool. Containers may explode in the heat of a fire. Extinguishing media: For small fires, use dry chemical, carbon dioxide, water spray or alcohol-resistant foam. For large fires, use water spray, fog, or alcohol-resistant foam. Use water spray to cool fire-exposed containers. Water may be ineffective. Do NOT use straight streams of water.
Fire potential
HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.
Hazards
Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers.
Combustion products
Toxic fumes of POx
Health
1
 
Flammability
3
 
 
Reactivity
1
 

Health.
Exposure limit(s)
NIOSH REL: TWA 2 ppm (10 mg/m3)
Poison_Class
4
Exposure effects
Reproductive effects have been reported in animals.
   Ingestion
May cause irritation of the digestive tract. May cause gastrointestinal irritation with nausea, vomiting and diarrhea. May be harmful if swallowed. Ingestion of large amounts may cause CNS depression.
   Inhalation
May cause respiratory tract irritation. The toxicological properties of this substance have not been fully investigated. Aspiration may lead to pulmonary edema. Vapors may cause dizziness or suffocation. May cause burning sensation in the chest.
   Skin
May cause skin irritation. May cause irritation and dermatitis. May cause cyanosis of the extremities.
   Eyes
May cause eye irritation. May cause chemical conjunctivitis and corneal damage.

First aid
 
   Ingestion
Get medical aid. Do NOT induce vomiting. If conscious and alert, rinse mouth and drink 2-4 cupfuls of milk or water.
   Inhalation
Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid.
   Skin
Get medical aid. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse.
   Eyes
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.

Transport.
UN number
2329
Response guide
Hazard class
3
Packing Group
III
 
USCG CHRIS Code
TPP
 
Std. Transport #
4909287
 
IMO Chemical Code
17
IMO Pollution Category
-
IMO Hazard code
S