Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Demephion-S

Demephion-S: phosphorothioic acid, o,o-dimethyl s-(2-(methylthio) ethyl) ester appears as a straw-colored liquid.

CAS 2587-90-8 Danger

01 · Identification

What Demephion-S is

Demephion-S: phosphorothioic acid, o,o-dimethyl s-(2-(methylthio) ethyl) ester appears as a straw-colored liquid. It boils at 230 °C.

Under the GHS it carries the signal word Danger.

CAS number2587-90-8
EC number219-971-9
Index number015-117-00-2

Other names for Demephion-S

  • demephion-S (ISO)
  • O,O-dimethyl S-2-methylthioethyl phosphorothioate

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to Demephion-S
CodeHazard statement
H300 Fatal if swallowed.
H311 Toxic in contact with skin.

Precautionary statements: P270, P280, P301, P302, P310, P330, P352

03 · Physical and chemical properties

Demephion-S properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Boiling point 230 °C (446 °F) at 760 mmHg DOE PAC
65 °C (149 °F) decomposes, at 0.1 mmHg (reduced pressure) CAMEO
Density 1.207 g/cm³ at 20 °C DOE PAC
1.218 g/cm³ at 25 °C CAMEO

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Handling and storage

Storing and handling Demephion-S

Reactivity

PHOSPHOROTHIOIC ACID, O,O-DIMETHYL S-(2-(METHYLTHIO) ETHYL) ESTER, like other thiophosphate esters, may react with strong reducing agents such as hydrides to give highly toxic and flammable phosphine gas. Partial oxidation by oxidizing agents may result in the release of toxic phosphorus oxides.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Demephion-S in the storage compatibility matrix →

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