Organosulfates are a class of

organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The s ...

s sharing a common

functional group In organic chemistry, a functional group is a substituent or moiety in a molecule that causes the molecule's characteristic chemical reactions. The same functional group will undergo the same or similar chemical reactions regardless of the res ...

with the structure R-O-SO₃⁻. The SO₄ core is a

sulfate The sulfate or sulphate ion is a polyatomic anion with the empirical formula . Salts, acid derivatives, and peroxides of sulfate are widely used in industry. Sulfates occur widely in everyday life. Sulfates are salts of sulfuric acid and many ...

group and the R group is any organic residue. All organosulfates are formally

ester In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides are f ...

s derived from

alcohol Alcohol most commonly refers to: * Alcohol (chemistry), an organic compound in which a hydroxyl group is bound to a carbon atom * Alcohol (drug), an intoxicant found in alcoholic drinks Alcohol may also refer to: Chemicals * Ethanol, one of sev ...

s and

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

, although many are not prepared in this way. Many sulfate esters are used in detergents, and some are useful

reagent In chemistry, a reagent ( ) or analytical reagent is a substance or compound added to a system to cause a chemical reaction, or test if one occurs. The terms ''reactant'' and ''reagent'' are often used interchangeably, but reactant specifies a ...

s. Alkyl sulfates consist of a

hydrophobic In chemistry, hydrophobicity is the physical property of a molecule that is seemingly repelled from a mass of water (known as a hydrophobe). In contrast, hydrophiles are attracted to water. Hydrophobic molecules tend to be nonpolar and, t ...

hydrocarbon chain, a polar

group (containing an anion) and either a cation or

amine In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituent suc ...

to neutralize the sulfate group. Examples include:

sodium lauryl sulfate Sodium dodecyl sulfate (SDS) or sodium lauryl sulfate (SLS), sometimes written sodium laurilsulfate, is an organic compound with the formula . It is an anionic surfactant used in many cleaning and hygiene products. This compound is the sodium salt ...

(also known as sulfuric acid mono dodecyl ester sodium salt) and related potassium and ammonium salts.

Applications

Alkyl sulfates are commonly used as an anionic surfactant in liquid soaps and detergents used to clean wool, as surface cleaners, and as active ingredients in laundry detergents, shampoos and conditioners. They can also be found in household products such as toothpaste, antacids, cosmetics and foods. Generally they are found in consumer products at concentrations ranging from 3-20%. In 2003 approximately 118,000 t/a of alkyl sulfates were used in the US

Synthetic organosulfates

A common example is

, with the formula CH₃(CH₂)₁₁OSO₃Na. Also common in consumer products are the sulfate esters of

ethoxylated Ethoxylation is a chemical reaction in which ethylene oxide adds to a substrate. It is the most widely practiced alkoxylation, which involves the addition of epoxides to substrates. In the usual application, alcohols and phenols are converted in ...

fatty alcohols such as those derived from lauryl alcohol. An example is

sodium laureth sulfate Sodium laureth sulfate (SLES), an accepted contraction of sodium lauryl ether sulfate (SLES), also called sodium alkylethersulfate, is an anionic detergent and surfactant found in many personal care products (soaps, shampoos, toothpaste, etc.) a ...

, an ingredient in some

cosmetics Cosmetics are constituted mixtures of chemical compounds derived from either natural sources, or synthetically created ones. Cosmetics have various purposes. Those designed for personal care and skin care can be used to cleanse or protect ...

. Alkylsulfate can be produced from alcohols, which in turn are obtained by

hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organic c ...

of animal or vegetable oils and fats or using the

Ziegler process In organic chemistry, the Ziegler process (also called the Ziegler-Alfol synthesis) is a method for producing fatty alcohols from ethylene using an organoaluminium compound. The reaction produces linear primary alcohols with an even numbered carbon ...

or through

oxo synthesis Hydroformylation, also known as oxo synthesis or oxo process, is an industrial process for the production of aldehydes from alkenes. This chemical reaction entails the net addition of a formyl group (CHO) and a hydrogen atom to a carbon-carbon d ...

. If produced from

oleochemical Oleochemistry is the study of vegetable oils and animal oils and fats, and oleochemicals derived from these fats and oils. The resulting product can be called oleochemicals (from Latin: oleum "olive oil"). The major product of this industry is soap, ...

feedstock or the Ziegler process, the

hydrocarbon In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or ...

chain of the alcohol will be linear. If derived using the oxo process, a low level of branching will appear usually with a methyl or ethyl group at the C-2 position, containing even and odd amounts of alkyl chains. These alcohols react with

chlorosulfuric acid Chlorosulfuric acid (IUPAC name: sulfurochloridic acid) is the inorganic compound with the formula HSO3Cl. It is also known as chlorosulfonic acid, being the sulfonic acid of chlorine. It is a distillable, colorless liquid which is hygroscopic and ...

: :ClSO₃H + ROH → ROSO₃H + HCl Alternatively, alcohols can be converted to the half sulfate esters using

sulfur trioxide Sulfur trioxide (alternative spelling sulphur trioxide, also known as ''nisso sulfan'') is the chemical compound with the formula SO3. It has been described as "unquestionably the most important economically" sulfur oxide. It is prepared on an ind ...

: :SO₃ + ROH → ROSO₃H Some organosulfates can be prepared by the

Elbs persulfate oxidation The Elbs persulfate oxidation is the organic reaction of phenols with alkaline potassium persulfate to form ''para''-diphenols. The reaction is generally performed in water at room temperatures or below, using equimolar quantities of reagents. ...

of phenols and the

Boyland–Sims oxidation The Boyland–Sims oxidation is the chemical reaction of anilines with alkaline potassium persulfate, which after hydrolysis forms ''ortho''-hydroxyl anilines. The reaction is generally performed in water at room temperatures or below, using equimo ...

of anilines.

Dialkylsulfates

A less common family of organosulfates have the formula RO-SO₂-OR'. They are prepared from sulfuric acid and the alcohol. The main examples are

diethyl sulfate Diethyl sulfate (DES) is a highly toxic, combustible, and likely carcinogenic chemical compound with the formula (C2H5)2SO4. It occurs as a colorless, oily liquid with a faint peppermint odor and is corrosive to tissue and metals. Diethyl sulfate ...

and

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 agent ...

, colourless liquids that are used as

s in

organic synthesis Organic synthesis is a special branch of chemical synthesis and is concerned with the intentional construction of organic compounds. Organic molecules are often more complex than inorganic compounds, and their synthesis has developed into one o ...

. These compounds are potentially dangerous

alkylating agent Alkylation is the transfer of an alkyl group from one molecule to another. 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 al ...

s. Dialkylsulfates do not occur in nature.

Natural sulfate esters

Heparin is a medication and naturally occurring organosulfate. Several classes of sulfate esters exist in nature. Especially common are sugar derivatives such as

keratan sulfate Keratan sulfate (KS), also called keratosulfate, is any of several sulfated glycosaminoglycans (structural carbohydrates) that have been found especially in the cornea, cartilage, and bone. It is also synthesized in the central nervous system wh ...

chondroitin sulfate Chondroitin sulfate is a sulfated glycosaminoglycan (GAG) composed of a chain of alternating sugars ( N-acetylgalactosamine and glucuronic acid). It is usually found attached to proteins as part of a proteoglycan. A chondroitin chain can have over ...

, and the anticoagulant

heparin Heparin, also known as unfractionated heparin (UFH), is a medication and naturally occurring glycosaminoglycan. Since heparins depend on the activity of antithrombin, they are considered anticoagulants. Specifically it is also used in the treatm ...

Post-translational modification Post-translational modification (PTM) is the covalent and generally enzymatic modification of proteins following protein biosynthesis. This process occurs in the endoplasmic reticulum and the golgi apparatus. Proteins are synthesized by ribosom ...

s of some proteins entail sulfation, often at the phenol group of

tyrosine -Tyrosine or tyrosine (symbol Tyr or Y) or 4-hydroxyphenylalanine is one of the 20 standard amino acids that are used by cells to synthesize proteins. It is a non-essential amino acid with a polar side group. The word "tyrosine" is from the Gr ...

residues. A steroidal sulfate is estradiol sulfate, a latent precursor to the hormone estrogen. A major portion of soil sulfur is in the form of sulfate esters.

Metabolism

Sulfate is an inert anion, so nature activates it by the formation of ester derivative of adenosine 5'-phosphosulfate (APS) and 3'-phosphoadenosine-5'-phosphosulfate (PAPS). Many organisms utilize these reactions for metabolic purposes or for the

biosynthesis Biosynthesis is a multi-step, enzyme- catalyzed process where substrates are converted into more complex products in living organisms. In biosynthesis, simple compounds are modified, converted into other compounds, or joined to form macromolecule ...

of sulfur compounds required for life. The formation and hydrolysis of natural sulfate esters are catalyzed by sulfatases (aka sulfohydrolases).

Safety

Because they are widely used in commercial products, the safety aspects of organosulfates are heavily investigated.

Human Health

Alkyl sulfates if ingested are well-absorbed and are metabolized into a C₃, C₄ or C₅ sulfate and an additional metabolite. The highest irritant of the alkyl sulfates is sodium laurylsulfate, with the threshold before irritation at a concentration of 20%. Surfactants in consumer products are typically mixed, reducing likelihood of irritation. According to OECD TG 406, alkyl sulfates in animal studies were not found to be skin sensitizers. Laboratory studies have not found alkyl sulfates to be

genotoxic Genotoxicity is the property of chemical agents that damage the genetic information within a cell causing mutations, which may lead to cancer. While genotoxicity is often confused with mutagenicity, all mutagens are genotoxic, but some genotoxic su ...

mutagenic In genetics, a mutagen is a physical or chemical agent that permanently changes genetic material, usually DNA, in an organism and thus increases the frequency of mutations above the natural background level. As many mutations can cause cancer in ...

carcinogenic A carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis (the formation of cancer). This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes. Several radioactive substan ...

. No long-term reproductive effects have been found.

Environment

The primary disposal of alkyl sulfate from used commercial products is wastewater. The concentration of alkylsulfates in effluent from waste water treatment plants (WWTP) has been measured at and lower. Alkyl sulfates biodegrade easily, even starting likely before reaching the WWTP. Once at the treatment plant, they are rapidly removed by

biodegradation Biodegradation is the breakdown of organic matter by microorganisms, such as bacteria and fungi. It is generally assumed to be a natural process, which differentiates it from composting. Composting is a human-driven process in which biodegradat ...

. Invertebrates were found to be the most-sensitive trophic group to alkyl sulfates. Sodium laurylsulfate tested on ''Uronema parduczi'', a protozoan, was found to have the lowest effect value with the 20 h-EC5 being . Chronic exposure tests with C₁₂ to C₁₈ with the invertebrate '' Ceriodaphnia dubia'' found the highest toxicity is with C₁₄ ( NOEC was 0.045 mg/L). In terms of thermal stability, alkyl sulfates degrade well before reaching their boiling point due to low vapor pressure (for C_8-18 from 10-11 to 10-15 hPa). Soil sorption is proportional to carbon chain length, with a length of 14 and more having the highest sorption rate. Soil concentrations have been found to vary from {{convert , 0.0035, to, 0.21, mg/kg, oz/lb, sigfig=2 dw.