Diethyl sulfate (DES) is an organosulfur compound with the

formula In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwe ...

(C₂H₅)₂SO₄. It occurs as a colorless, oily liquid with a faint

peppermint Peppermint (''Mentha'' × ''piperita'') is a Hybrid (biology), hybrid species of Mentha, mint, a cross between Mentha aquatica, watermint and spearmint. Indigenous to Europe and the Middle East, the plant is now widely spread and cultivated in m ...

odor. It is

toxic Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subst ...

combustible A combustible material is a material that can burn (i.e., sustain a flame) in air under certain conditions. A material is flammable if it ignites easily at ambient temperatures. In other words, a combustible material ignites with some effort a ...

, and likely

carcinogen A carcinogen () is any agent that promotes the development of cancer. Carcinogens can include synthetic chemicals, naturally occurring substances, physical agents such as ionizing and non-ionizing radiation, and biologic agents such as viruse ...

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

. Diethyl sulfate is used as an ethylating agent.

Structure and properties

Although the formula for diethyl sulfate is typically written (C₂H₅)₂SO₄, a more descriptive formula would be (C₂H₅O)₂SO₂. It is a diester of sulfuric acid. Sulfur is tetrahedral. Diethyl sulfate hydrolyzes readily, forming

ethanol Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formula . It is an Alcohol (chemistry), alcohol, with its formula also written as , or EtOH, where Et is the ps ...

and

ethyl sulfate Ethyl sulfate (IUPAC name: ethyl hydrogen sulfate), also known as sulfovinic acid, is an organic chemical compound used as an intermediate in the production of ethanol from ethylene. It is the ethyl ester of sulfuric acid. History This substanc ...

. Eventually

sulfuric acid Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (English in the Commonwealth of Nations, Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, ...

is formed with excess

water Water is an inorganic compound with the chemical formula . It is a transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known liv ...

Reactions

Diethyl sulfate is used to an alkylating agent to prepare ethyl ethers, ethyl amines and ammonium salts, and ethyl thioethers. In preparing ethyl esters of fatty acids, both equivalents of the ethyl electrophile are transferred, unlike the usual alkylation of phenoxides: : Both dimethyl sulfate and diethyl sulfate react with inorganic nucleophiles as well. For example,

potassium iodide Potassium iodide is a chemical compound, medication, and dietary supplement. It is a medication used for treating hyperthyroidism, in radiation emergencies, and for protecting the thyroid gland when certain types of radiopharmaceuticals are u ...

gives ethyl iodide.

Preparation

Diethyl sulfate cannot be prepared efficiently analogously to the method used for

dimethyl sulfate Dimethyl sulfate (DMS) is a chemical compound with formula (CH3O)2SO2. As the diester of methanol and sulfuric acid, its formula is often written as ( CH3)2 SO4 or Me2SO4, where CH3 or Me is methyl. Me2SO4 is mainly used as a methylating agen ...

. The reaction of

oleum Oleum (Latin ''oleum'', meaning oil), or fuming sulfuric acid, is a term referring to solutions of various compositions of sulfur trioxide in sulfuric acid, or sometimes more specifically to disulfuric acid (also known as pyrosulfuric acid). Ol ...

with

diethyl ether Diethyl ether, or simply ether, is an organic compound with the chemical formula , sometimes abbreviated as . It is a colourless, highly Volatility (chemistry), volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It belongs ...

results in excessive oxidation of the ethyl groups. Instead, diethyl sulfate is prepared in two steps starting from chlorosulfuric acid: : The resulting ethyl sulfate is then heated with

sodium sulfate Sodium sulfate (also known as sodium sulphate or sulfate of soda) is the inorganic compound with formula Na2SO4 as well as several related hydrates. All forms are white solids that are highly soluble in water. With an annual production of 6 mill ...

, leading to a redistribution reaction: :

Safety

Like other strong

alkylating agent Alkylation is a chemical reaction that entails transfer of an alkyl group. The alkyl group may be transferred as an alkyl carbocation, a free radical, a carbanion, or a carbene (or their equivalents). Alkylating agents are reagents for effecting ...

s and especially dimethyl sulfate, diethyl sulfate is toxic and genotoxic. It is classified as a Group 2A (probably carcinogenic to humans) carcinogen by the IARC. Experimentation with animals has suggested this compound is likely carcinogenic to humans as it was implicated in the development of

laryngeal cancer Laryngeal cancer is a kind of cancer that can develop in any part of the larynx (voice box). It is typically a squamous-cell carcinoma, reflecting its origin from the epithelium of the larynx. The prognosis is affected by the location of the tumo ...

. Evidence of the effects of this chemical compound on reproductive or developmental health is also lacking.

Neutralization

Dialkyl sulfates can be rendered nontoxic by treatment with

aqueous ammonia Ammonia solution, also known as ammonia water, ammonium hydroxide, ammoniacal liquor, ammonia liquor, aqua ammonia, aqueous ammonia, or (inaccurately) ammonia, is a solution of ammonia in water. It can be denoted by the symbols NH3(aq). Although ...

References

External links

* * * {{ cite web , url = http://monographs.iarc.fr/ENG/Monographs/vol71/mono71-92.pdf , year = 1992 , volume = 71 , publisher = IARC , series = IARC Monographs , title = Diethyl sulfate Ethylating agents IARC Group 2A carcinogens Ethyl esters Sulfate esters