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215112

Sigma-Aldrich

Phosphorous acid

99%

Synonym(s):

Phosphonic acid

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About This Item

Empirical Formula (Hill Notation):
H3O3P
CAS Number:
13598-36-2
Molecular Weight:
82.00
EC Number:
237-066-7
MDL number:
MFCD00137258
UNSPSC Code:
12352106
PubChem Substance ID:
329752161
NACRES:
NA.21

Quality Level

100

Assay

99%

form

crystals or chunks
flakes

solubility

water: soluble

density

1.651 g/mL at 25 °C (lit.)

SMILES string

[H]P(O)(O)=O

InChI

1S/H3O3P/c1-4(2)3/h4H,(H2,1,2,3)

InChI key

ABLZXFCXXLZCGV-UHFFFAOYSA-N

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General description

Phosphorous acid (or phosphonic acid) is a phosphorus oxoacid commonly used as an intermediate in chemical synthesis for the production of various phosphorus compounds. It is also used as a strong reducing agent in organic synthesis.

Application

Phosphorous acid (H3PO3, orthophosphorous acid) may be used as one of the reaction components for the synthesis of the following:
  • α-aminomethylphosphonic acids via Mannich-Type Multicomponent Reaction
  • 1-aminoalkanephosphonic acids via amidoalkylation followed by hydrolysis
  • N-protected α-aminophosphonic acids (phospho-isosteres of natural amino acids) via amidoalkylation reaction

Pictograms

CorrosionExclamation mark
GHS05,GHS07

Signal Word

Danger

Hazard Statements

H290,H302,H314

Hazard Classifications

Acute Tox. 4 Oral - Eye Dam. 1 - Met. Corr. 1 - Skin Corr. 1A

Storage Class Code

8A - Combustible corrosive hazardous materials

WGK

WGK 1

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Regulatory Information

危险化学品

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Certificates of Analysis (COA)

Lot/Batch Number
MKCS2013
MKCS4814
MKCP8300
MKCP7746
MKCM6736

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    If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.

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    Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product. 

  5. What is Product 215112, Phosphorous acid, soluble in?

    Phosphorous acid is appreciably soluble in water.

  6. What is the melting point of Product 215112, Phosphorous acid?

    The melting point of phosphorous acid is approximately 74°C.

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    Ask a Scientist here.

Amidoalkylation of phosphorous acid.
Vinyukov AV, et al.
Russ. J. Gen. Chem., 85(2), 366-369 (2015)
Ping Yin et al.
Bioresource technology, 110, 258-263 (2012-02-22)
Esterification of oleic acid with ethanol catalyzed by organophosphonic acid-functionalized silica SG-T-P was optimized using response surface methodology (RSM). The interactive effect of catalyst to FFA weight ratio and molar ratio of alcohol to acid were more significant than that
Emily B Pentzer et al.
Advanced materials (Deerfield Beach, Fla.), 24(17), 2254-2258 (2012-03-28)
Poly(3-hexyl thiophene) containing chain-end thiols or phosphonic acids is crystallized to yield nanowires with the functional groups at the wire edges. CdSe quantum dots and nanorods associate with these fibrils, leading to 'superhighways' that consist of alternating parallel lanes of
Marina Borges Osorio et al.
Plant physiology, 181(1), 332-352 (2019-07-03)
Phosphorus (P) is an essential macronutrient for all living organisms and limits plant growth. Four proteins comprising a single SYG1/Pho81/XPR1 (SPX) domain, SPX1 to SPX4, are putative phosphate-dependent inhibitors of Arabidopsis (Arabidopsis thaliana) PHOSPHATE STARVATION RESPONSE1 (PHR1), the master transcriptional
Amidoalkylation of phosphorous acid.
Oleksyszyn J and Gruszeckae.
Tetsu to Hagane, 22(36), 3537-3540 (1981)
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