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

Dimethyl Sulfate

Dimethyl Sulfate is a colorless oily liquid and is odorless.

CAS 77-78-1 C2H6O4S 126.13 g/mol Danger

01 · Identification

What Dimethyl Sulfate is

Dimethyl Sulfate is a colorless oily liquid and is odorless. Its molecular formula is C2H6O4S and its molecular weight is 126.13 g/mol. It boils at 188 °C, melts at -27 °C.

Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).

CAS number77-78-1
EC number201-058-1
Index number016-023-00-4
Molecular formulaC2H6O4S
Molecular weight126.13 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

Other names for Dimethyl Sulfate

  • dimethyl sulphate

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 Dimethyl Sulfate
CodeHazard statement
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H341 Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H330 Fatal if inhaled.
H301 Toxic if swallowed.
H314 Causes severe skin burns and eye damage.
H317 May cause an allergic skin reaction.

Precautionary statements: P201, P260, P261, P270, P271, P272, P280, P301, P304, P308, P310, P313, P330, P331, P333

03 · Physical and chemical properties

Dimethyl Sulfate 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 188 °C (370.4 °F) approximate HSDB
187.78 °C (370 °F) approximate CAMEO
187.78 °C (370 °F) decomposes NIOSH
Melting point -27 °C (-16.6 °F) HSDB
-31.67 °C (-25 °F) NIOSH
-31.75 °C (-25.1 °F) CAMEO
Density 1.33 g/cm³ NIOSH
1.3322 g/cm³ at 20 °C HSDB
1.3283 g/cm³ at 20 °C CAMEO
Solubility Sol in ether, dioxane, acetone, aromatic hydrocarbons. HSDB
Sparingly sol in carbon disulfide, aliphatic hydrocarbons. HSDB
Miscible in ethanol; soluble in ethyl ether, carbon tetrachloride and benzene; insoluble in carbon disulfide HSDB
Vapor pressure 0.1 mmHg NIOSH
0.5 mmHg at 20 °C CAMEO
0.677 mmHg at 25 °C HSDB
Flash point 83.33 °C (182 °F) HSDB
Autoignition temperature 187.78 °C (370 °F) HSDB
470 °C (878 °F) ICSC
Lower explosive limit (LEL) 3.6 % by volume HSDB
Class IIIA Combustible Liquid: Fl.P. at or above 140 °F and below 200 °F. NIOSH
Upper explosive limit (UEL) 23.3 % by volume HSDB
Moderate fire potential when exposed to heat or flame. (EPA, 1998) CAMEO
Vapor density 4.35 (air = 1) HSDB
4.4 (air = 1) ICSC
Corrosivity Corrosive HSDB

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

04 · Handling and storage

Storing and handling Dimethyl Sulfate

Storage conditions

PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practicable to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator, or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired ... . Facilities for dispensing ... should be contiguous to storage area. /Chemical Carcinogens/

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Can react with oxidizing materials.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

Pure DIMETHYL SULFATE and concentrated aqueous ammonia react extremely violently with one another, as is the case for tertiary organic bases, [NFPA 491M, 1991]. Dimethyl sulfate ignites in contact with unheated barium chlorite, due to the rapid formation of unstable methyl chlorite. The product of methylating an unnamed material at 110 °C was allowed to remain in a reactor for 80 min. before the reactor exploded. This involved a sulfur ester such as dimethyl sulfate, [MCA Case History No. 1786].

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Dimethyl Sulfate in the storage compatibility matrix →

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