METHYLPHOSPHONIC ACID

Synonym(s):MPA

CAS NO.：993-13-5
Empirical Formula: CH5O3P
Molecular Weight: 96.02
MDL number: MFCD00002137
EINECS: 213-607-2
SAFETY DATA SHEET (SDS)
Update Date: 2025-12-31 14:38:37

What is METHYLPHOSPHONIC ACID?

Chemical properties

white crystals or flakes

The Uses of METHYLPHOSPHONIC ACID

Methylphosphonic acid is used to produce methyl-phosphonic acid dichloride by chlorination.

The Uses of METHYLPHOSPHONIC ACID

Organic synthesis.

Definition

ChEBI: Methylphosphonic acid is a one-carbon compound that is phosphonic acid in which the hydrogen attached to the phosphorus is substituted by a methyl group. It is a one-carbon compound and a member of phosphonic acids. It is functionally related to a phosphonic acid. It is a conjugate acid of a methylphosphonate(1-).

What are the applications of Application

Methylphosphonic acid is used in the production of lubricant additives and for treating textiles.

Flammability and Explosibility

Not classified

Purification Methods

Methylphosphonic acid [993-13-5] M 96.0, m 104-106o, 105-107o, 108o, pK 1 2.12, pK 2 7.29. If it tests for Cl-, then add H2O and evaporate to dryness, repeat several times till free from Cl-. The residue solidifies to a wax-like solid. Alternatively, dissolve the acid in the minimum volume of H2O, add charcoal, warm, filter and evaporate to dryness in a vacuum over P2O5. [Kosolapoff J Am Chem Soc 75 3379 1953.] The di-Na salt is prepared from 24g of acid in 50mL of dry EtOH, and a solution of 23g Na dissolved in 400mL EtOH is added. A white precipitate is formed, but the mixture is refluxed for 30minutes to complete the reaction. Filter off the solid and recrystallise it from 50% EtOH. Dry the crystals in a vacuum desiccator. [Thompson J Chem Soc 3292 1952, Beilstein 4 IV 3498.]

Properties of METHYLPHOSPHONIC ACID

Melting point:	105-107 °C(lit.)
Boiling point:	265.2±23.0 °C(Predicted)
Density	1.495±0.06 g/cm3(Predicted)
vapor pressure	0Pa at 20℃
storage temp.	-20°C
solubility	H2O: soluble2.88 g in 30 mL, clear, colorless
pka	pK1:2.38;pK2:7.74 (25°C)
form	Crystalline Powder
color	White to off-white
PH	0.9-1.4
Water Solubility	Soluble in water and alcohol.
λmax	λ: 260 nm Amax: ≤0.05 λ: 280 nm Amax: ≤0.04
Sensitive	Hygroscopic
BRN	1739372
Stability:	Stable. Incompatible with strong oxidizing agents, strong bases.
EPA Substance Registry System	Phosphonic acid, P-methyl- (993-13-5)

Safety information for METHYLPHOSPHONIC ACID

Signal word	Danger
Pictogram(s)	Corrosion Corrosives GHS05
GHS Hazard Statements	H314:Skin corrosion/irritation
Precautionary Statement Codes	P260:Do not breathe dust/fume/gas/mist/vapours/spray. P280:Wear protective gloves/protective clothing/eye protection/face protection. P303+P361+P353:IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower. P305+P351+P338:IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.