Dimethyl sulfate

Description

Dimethyl sulfate (chemical formula: (CH3O)2SO2) is an odorless, corrosive, oily liquid which can release toxic fumes during heating. It can be synthesized through the esterification of sulfuric acid with methanol, and alternatively by the distillation of methyl hydrogen sulfate.

In industry, dimethyl sulfate is used as a methylating agent for the manufacture of many organic chemicals. It can be used for methylation of phenols, amines, and thiol. Moreover, it can be used for base sequencing and DNA chain cleavage since it can rupture the imidazole rings present in guanine. It can also be used for protein-DNA interaction analysis. However, its vapor is toxic to eyes and lungs, can do harm to our body. It is a potential carcinogen based on known experimental data.

Chemical Properties

Dimethyl sulfate is a colorless, oily liquid that is slightly soluble in water. It has a faint, onion-like odor; the odor threshold has not been established. The vapor pressure for dimethyl sulfate is 0.5 mm Hg at 20 °C, and it has a log octanol/water partition coefficient (log Kow ) of 0.032.

Uses

Dimethyl sulphate has been used since the beginning of the century as a methylating agent in the preparation of organic chemical products and colouring agents, in the perfume industry, and in other processes. It is a colourless or yellowish liquid of oily consistency which vaporizes at 50℃. and has a slight piquant smell. Both the liquid and the vapour are vesicants and by virtue of this property may be used in warfare.

References

https://en.wikipedia.org/wiki/Dimethyl_sulfate
https://pubchem.ncbi.nlm.nih.gov/compound/dimethyl_sulfate#section=Top

Description

Dimethyl sulfate is a colorless, oily liquid with a faint, onionlike odor. It is soluble in water, ether, dioxane, acetone, benzene, and other aromatic hydrocarbons, miscible with ethanol, and sparingly soluble in carbon disulfide. It is stable under normal temperatures and pressures, but hydrolyzes rapidly in water at or above 18 ℃.
Dimethyl sulfate has been produced commercially since at least the 1920s. One production method is continuous reaction of dimethyl ether with sulfur trioxide. In 2009, dimethyl sulfate was produced by 33 manufacturers worldwide, including 1 in the United States, 14 in China, 5 in India, 5 in Europe, 6 in East Asia, and 2 in Mexico, and was available from 44 suppliers, including 16 US suppliers. There are no data on US imports or exports of dimethyl sulfate. Reports filed from 1986 through 2002 under the US Environmental Protection Agency’s Toxic Substances Control Act Inventory Update Rule indicate that US production plus imports of dimethyl sulfate totaled 10–50 million pounds. The simplest way of synthesizing dimethyl sulfate is by esterification of sulfuric acid with methanol as follows:2CH3OH+ H2SO4→(CH3)2SO4 + 2H2O

Chemical Properties

Dimethyl sulfate is essentially odorless. The specific gravity of this colorless, corrosive, oily liquid is 1.3322 g/cm3. Dimethyl sulfate is soluble in ether, dioxane, acetone, benzene, and other aromatic hydrocarbons. It is sparingly soluble in carbon disulfide and aliphatic hydrocarbons, and only slightly soluble in water (28 g/l at 18 °C) (O'Neil, 2006).

Uses

Dimethyl sulfate is a strong alkylating agent and might also react with the carboxylic acid substrate, further reducing the DMS concentration in the mixture. It is used as a methylating agent in themanufacture of many organic compounds,such as, phenols and thiols. Also, it is used inthe manufacture of dyes and perfumes, andas an intermediate for quaternary ammoniumsalts. It was used in the past as a militarypoison.

Application

Dimethyl Sulfate is a diester of methanol and sulfuric acid. Dimethyl Sulfate is commonly used as a reagent for the methylation of phenols, amines, and thiols. Dimethyl Sulfate is an effective and widely used probe for sequence-specific protein-DNA interactions.

Definition

ChEBI: Dimethyl sulfate is the dimethyl ester of sulfuric acid. It has a role as an alkylating agent and an immunosuppressive agent.

Preparation

Dimethyl sulfate is prepared by distillation of an oleum/methanol mixture; technical production using dimethyl ether and SO3 has also been reported (NLM, 2013).

General Description

Dimethyl sulfate is a colorless oily liquid, odorless to a faint onion-like odor. Dimethyl sulfate is very toxic by inhalation. Dimethyl sulfate is a combustible liquid and has a flash point of 182°F. Dimethyl sulfate is slightly soluble in water and decomposed by water to give sulfuric acid with evolution of heat. Dimethyl sulfate is corrosive to metals and tissue.

Air & Water Reactions

Water soluble.

Reactivity Profile

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 alloyed 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].

Health Hazard

Dimethyl sulfate is extremely hazardous because of its lack of warning properties and delayed toxic effects. The vapor of this compound is extremely irritating to the skin, eyes, and respiratory tract, and contact with the liquid can cause very severe burns to the eyes and skin. Ingestion of dimethyl sulfate causes burns to the mouth, throat, and gastrointestinal tract. The effects of overexposure to dimethyl sulfate vapor may be delayed. After a latent period of 10 hours or more, headache and severe pain to the eyes upon exposure to light may occur, followed by cough, tightness of the chest, shortness of breath, difficulty in swallowing and speaking, vomiting, diarrhea, and painful urination. Fatal pulmonary edema may develop. Systemic effects of dimethyl sulfate include damage to the liver and kidneys. Dimethyl sulfate is listed by IARC in Group 2A ("probable human carcinogen") and is classified as a "select carcinogen" under the criteria of the OSHA Laboratory Standard. Data indicate that dimethyl sulfate does not specifically harm unborn animals; dimethyl sulfate is not a developmental toxin. It is a strong alkylating agent and does produce genetic damage in animals and in bacterial and mammalian cell cultures.

Flammability and Explosibility

Dimethyl sulfate is a combustible liquid (NFPA rating = 2). Toxic dimethyl sulfate vapors are produced in a fire. Carbon dioxide or dry chemical extinguishers should be used to fight dimethyl sulfate fires.

Potential Exposure

Tumorigen,Mutagen; Reproductive Effector; Human Data; PrimaryIrritant. Industrial use of dimethyl sulfate is based upon itsmethylating properties. It is used as an alkylating agent; inthe manufacture of methyl esters, ethers, and amines; indyes, drugs, perfume, phenol derivatives, and other organicchemicals; as a solvent in the separation of mineral oils; asan intermediate in the manufacture of sodium acetylide synthesis, as well as many pharmaceuticals and pesticides.

First aid

If this chemical gets into the eyes, remove anycontact lenses at once and irrigate immediately for at least30 min, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts theskin, remove contaminated clothing and wash immediatelywith soap and water. Seek medical attention immediately. Ifthis chemical has been inhaled, remove from exposure,begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR ifheart action has stopped. Transfer promptly to a medicalfacility. When this chemical has been swallowed, get medical attention. If victim is conscious, administer water ormilk. Do not induce vomiting. Medical observation isrecommended for 2448 h after breathing overexposure, aspulmonary edema may be delayed. As first aid for pulmonary edema, a doctor or authorized paramedic may consideradministering a corticosteroid spray.

Carcinogenicity

Dimethyl sulfate is reasonably anticipated to be a human carcinogenbased on sufficient evidence of carcinogenicity from studies in experimental animals.

Environmental Fate

Chemical/Physical. Hydrolyzes in water (half-life = 1.2 h) to methanol and sulfuric acid (Robertson and Sugamori, 1966) via the intermediate methyl sulfuric acid (Du Pont, 1999a)

storage

work with dimethyl sulfate should be conducted in a fume hood to prevent exposure by inhalation, and appropriate impermeable gloves and safety goggles should be worn at all times to prevent skin and eye contact.

Shipping

This compound requires a shipping label of“POISONOUS/TOXIC MATERIALS, CORROSIVE.” Itfalls in Hazard Class 6.1 and Packing Group I.

Incompatibilities

Dimethyl sulfate can react violently with ammonium hydroxide, sodium azide, and strong oxidizers.

Waste Disposal

Excess dimethyl sulfate and waste material containing this substance should be placed in a covered metal container, clearly labeled, and handled according to your institution's waste disposal guidelines.