Enantioselective synthesis called asymmetric synthesis, is a form of chemical synthesis. It is defined by IUPAC as: a chemical reaction in which one or more new elements of chirality are formed in a substrate molecule and which produces the stereoisomeric products in unequal amounts. Put more simply: it is the synthesis of a compound by a method that favors the formation of a specific enantiomer or diastereomer. Enantioselective synthesis is a key process in modern chemistry and is important in the field of pharmaceuticals, as the different enantiomers or diastereomers of a molecule have different biological activity. Many of the building blocks of biological systems such as sugars and amino acids are produced as one enantiomer; as a result living systems possess a high degree of chemical chirality and will react differently with the various enantiomers of a given compound. Examples of this selectivity include: Flavour: the artificial sweetener aspartame has two enantiomers. L-aspartame tastes sweet.
Odor: R--carvone smells like spearmint whereas S--carvone smells like caraway. Drug effectiveness: the antidepressant drug Citalopram is sold as a racemic mixture. However, studies have shown that only the - enantiomer is responsible for the drug's beneficial effects. Drug safety: D‑penicillamine is used in chelation therapy and for the treatment of rheumatoid arthritis whereas L‑penicillamine is toxic as it inhibits the action of pyridoxine, an essential B vitamin; as such enantioselective synthesis is of great importance but it can be difficult to achieve. Enantiomers possess identical enthalpies and entropies and hence should be produced in equal amounts by an undirected process – leading to a racemic mixture. Enantioselective synthesis can be achieved by using a chiral feature that favors the formation of one enantiomer over another through interactions at the transition state; this biasing is known as asymmetric induction and can involve chiral features in the substrate, catalyst, or environment and works by making the activation energy required to form one enantiomer lower than that of the opposing enantiomer.
Enantioselectivity is determined by the relative rates of an enantiodifferentiating step—the point at which one reactant can become either of two enantiomeric products. The rate constant, k, for a reaction is function of the activation energy of the reaction, sometimes called the energy barrier, is temperature-dependent. Using the Gibbs free energy of the energy barrier, ΔG*, means that the relative rates for opposing stereochemical outcomes at a given temperature, T, is: k 1 k 2 = 10 Δ Δ G ∗ T × 1.98 × 2.3 This temperature dependence means the rate difference, therefore the enantioselectivity, is greater at lower temperatures. As a result small energy-barrier differences can lead to a noticeable effect. In general, enantioselective catalysis are chiral coordination complexes. Catalysis is effective for a broader range of transformations than any other method of enantioselective synthesis; the catalysts are invariably rendered chiral by using chiral ligands. Most enantioselective catalysts are effective at low substrate/catalyst ratios.
Given their high efficiencies, they are suitable for industrial scale synthesis with expensive catalysts. A versatile example of enantioselective synthesis is asymmetric hydrogenation, used to reduce a wide variety of functional groups; the design of new catalysts is much dominated by the development of new classes of ligands. Certain ligands referred to as'privileged ligands', have been found to be effective in a wide range of reactions. In general however few catalysts are effective at more than one type of asymmetric reaction. For example, Noyori asymmetric hydrogenation with BINAP/Ru requires a β-ketone, although another catalyst, BINAP/diamine-Ru, widens the scope to α,β-alkenes and aromatic chemicals. A chiral auxiliary is an organic compound which couples to the starting material to form a new compound which can undergo enantioselective reactions via intramolecular asymmetric induction. At the end of the reaction the auxiliary is removed, under conditions that will not cause racemization of the product.
It is then recovered for future use. Chiral auxiliaries must be used in stoichiometric amounts to be effective and require additional synthetic steps to append and remove the auxiliary. However, in some cases the only available stereoselective methodology relies on chiral auxiliaries and these reactions tend to be versatile and well-studied, allowing the most time-efficient access to enantiomerically pure products. Additionally, the products of auxiliary-directed reactions are diastereomers, which enables their facile separation by methods such as column chromatography or crystallization. Biocatalysis makes use of biological compounds, ranging from isolated enzymes to living cells, to perform chemical transformations; the advantages of these reagents include high e.e.s and reagent specificity, as well as mild operating conditions and low environmental impact. Biocatalysts are more used in industry than in academic research.
Royal Society of Chemistry
The Royal Society of Chemistry is a learned society in the United Kingdom with the goal of "advancing the chemical sciences". It was formed in 1980 from the amalgamation of the Chemical Society, the Royal Institute of Chemistry, the Faraday Society, the Society for Analytical Chemistry with a new Royal Charter and the dual role of learned society and professional body. At its inception, the Society had a combined membership of 34,000 in the UK and a further 8,000 abroad; the headquarters of the Society are at Burlington House, London. It has offices in Thomas Graham House in Cambridge where RSC Publishing is based; the Society has offices in the United States at the University City Science Center, Philadelphia, in both Beijing and Shanghai and Bangalore, India. The organisation carries out research, publishes journals and databases, as well as hosting conferences and workshops, it is the professional body for chemistry in the UK, with the ability to award the status of Chartered Chemist and, through the Science Council the awards of Chartered Scientist, Registered Scientist and Registered Science Technician to suitably qualified candidates.
The designation FRSC is given to a group of elected Fellows of the society who have made major contributions to chemistry and other interface disciplines such as biological chemistry. The names of Fellows are published each year in The Times. Honorary Fellowship of the Society is awarded for distinguished service in the field of chemistry; the president is elected biennially and wears a badge in the form of a spoked wheel, with the standing figure of Joseph Priestley depicted in enamel in red and blue, on a hexagonal medallion in the centre. The rim of the wheel is gold, the twelve spokes are of non-tarnishable metals; the current president is Dame Carol V. Robinson. Past presidents of the society have been: The following are membership grades with post-nominals: Affiliate: The grade for students and those involved in chemistry who do not meet the requirements for the following grades. AMRSC: Associate Member, Royal Society of Chemistry The entry level for RSC membership, AMRSC is awarded to graduates in the chemical sciences.
MRSC: Member, Royal Society of Chemistry Awarded to graduates with at least 3 years' experience, who have acquired key skills through professional activity FRSC: Fellow of the Royal Society of Chemistry Fellowship may be awarded to nominees who have made an outstanding contribution to chemistry. HonFRSC: Honorary Fellow of the Society Honorary Fellowship is awarded for distinguished service in the field of chemistry. CChem: Chartered Chemist The award of CChem is considered separately from admission to a category of RSC membership. Candidates need to be MRSC or FRSC and demonstrate development of specific professional attributes and be in a job which requires their chemical knowledge and skills. CSci: Chartered Scientist The RSC is a licensed by the Science Council for the registration of Chartered Scientists. EurChem: European Chemist The RSC is a member of the European Communities Chemistry Council, can award this designation to Chartered Chemists. MChemA: Mastership in Chemical Analysis The RSC awards this postgraduate qualification, the UK statutory qualification for practice as a Public Analyst.
It requires candidates to submit a portfolio of suitable experience and to take theory papers and a one-day laboratory practical examination. The qualification GRSC was awarded from 1981 to 1995 for completion of college courses equivalent to an honours chemistry degree and overseen by the RSC, it replaced the GRIC offered by the Royal Institute of Chemistry. The society is organised around 9 divisions, based on subject areas, local sections, both in the United Kingdom and overseas. Divisions cover broad areas of chemistry but contain many special interest groups for more specific areas. Analytical Division for analytical chemistry and promoting the original aims of the Society for Analytical Chemistry. 12 Subject Groups. Dalton Division, named after John Dalton, for inorganic chemistry. 6 Subject Groups. Education Division for chemical education. 4 Subject Groups. Faraday Division, named after Michael Faraday, for physical chemistry and promoting the original aims of the Faraday Society. 14 Subject Groups.
Organic Division for organic chemistry. 6 Subject Groups. Chemical Biology Interface Division. 2 Subject Groups. Environment and Energy Division. 3 Subject Groups. Materials Chemistry Division. 4 Subject Groups. Industry and Technology Division. 13 Subject Groups. There are 12 subjects groups not attached to a division. There are 35 local sections covering the United Ireland. In countries of the Commonwealth of Nations and many other countries there are Local Representatives of the society and some activities; the society is a not-for-profit publisher: surplus made by its publishing business is invested to support its aim of advancing the chemical sciences. In addition to scientific journals, including its flagship journals Chemical Communications, Chemical Science and Chemical Society Reviews, the society publishes: Education in Chemistry for teachers. A free online journal for chemistry educators, Chemistry Education Research and Practice. A general chemistry magazine Chemistry World, sent monthly to all members of the Society throughout the world.
The editorial board consists of 10 industrial chemists. It was first published in January 2004, it replaced C
Chiral resolution in stereochemistry is a process for the separation of racemic compounds into their enantiomers. It is an important tool in the production of optically active drugs. Other terms with the same meaning are mechanical resolution. One disadvantage of chiral resolution of racemates compared to direct asymmetric synthesis of one of the enantiomers is that only 50% of a desired enantiomer is obtained. Several methods exist. 5-10% of all racemates are known to crystallize as mixtures of enantiopure crystals, so-called conglomerates. Louis Pasteur was the first to conduct chiral resolution when he discovered the concept of optical activity by the manual separation of left-handed and right-handed tartaric acid crystals in 1849. In 1882 he went on to demonstrate that by seeding a supersaturated solution of sodium ammonium tartrate with a d-crystal on one side of the reactor and a l-crystal on the opposite side, crystals of opposite handedness will form on the opposite sides of the reactor.
This type of resolution, called spontaneous resolution, has been demonstrated with racemic methadone. In a typical setup 50 grams dl-methadone concentrated. Two millimeter-sized d- and l-crystals are added and after stirring for 125 hours at 40 °C two large d- and l-crystals are recovered in 50% yield. Another form of direct crystallization is preferential crystallization called resolution by entrainment of one of the enantiomers. For example, an added seed of -hydrobenzoin to an ethanol solution of -hydrobenzoin will have the -enantiomer crystallizing out and after 15 cycles 97% optical purity can be obtained. Derivatization of racemic compounds is possible with optically pure reagents forming pairs of diastereomers which can be separated by conventional techniques in physical chemistry. Derivatization is possible by salt formation between a carboxylic acid. Simple deprotonation affords the pure enantiomer. Examples of chiral derivatizing agents are tartaric brucine; the method was introduced by Louis Pasteur in 1853 by resolving racemic tartaric acid with optically active -cinchotoxine.
One modern-day method of chiral resolution is used in the organic synthesis of the drug duloxetine: In one of its steps the racemic alcohol 1 is dissolved in a mixture of toluene and methanol to which solution is added optically active -mandelic acid 3. The alcohol -enantiomer forms an insoluble diastereomeric salt with the mandelic acid and can be filtered from the solution. Simple deprotonation with sodium hydroxide liberates free -alcohol. In the meanwhile the -alcohol remains in solution unaffected and is recycled back to the racemic mixture by epimerization with hydrochloric acid in toluene; this process is known as RRR synthesis. In chiral column chromatography the stationary phase is made chiral with similar resolving agents as described above
Acetaldehyde is an organic chemical compound with the formula CH3CHO, sometimes abbreviated by chemists as MeCHO. It is one of the most important aldehydes, occurring in nature and being produced on a large scale in industry. Acetaldehyde occurs in coffee and ripe fruit, is produced by plants, it is produced by the partial oxidation of ethanol by the liver enzyme alcohol dehydrogenase and is a contributing cause of hangover after alcohol consumption. Pathways of exposure include air, land, or groundwater, as well as drink and smoke. Consumption of disulfiram inhibits acetaldehyde dehydrogenase, the enzyme responsible for the metabolism of acetaldehyde, thereby causing it to build up in the body; the International Agency for Research on Cancer has listed acetaldehyde as a Group 1 carcinogen. Acetaldehyde is "one of the most found air toxins with cancer risk greater than one in a million". Acetaldehyde was first observed by the Swedish pharmacist/chemist Carl Wilhelm Scheele. In 1835, Liebig named it "aldehyde".
In 2003, global production was about 1 million tonnes. Before 1962, ethanol and acetylene were the major sources of acetaldehyde. Since ethylene is the dominant feedstock; the main method of production is the oxidation of ethylene by the Wacker process, which involves oxidation of ethylene using a homogeneous palladium/copper system: 2 CH2=CH2 + O2 → 2 CH3CHOIn the 1970s, the world capacity of the Wacker-Hoechst direct oxidation process exceeded 2 million tonnes annually. Smaller quantities can be prepared by the partial oxidation of ethanol in an exothermic reaction; this process is conducted over a silver catalyst at about 500–650 °C. CH3CH2OH + 1⁄2 O2 → CH3CHO + H2OThis method is one of the oldest routes for the industrial preparation of acetaldehyde. Prior to the Wacker process and the availability of cheap ethylene, acetaldehyde was produced by the hydration of acetylene; this reaction is catalyzed by mercury salts: C2H2 + Hg2+ + H2O → CH3CHO + HgThe mechanism involves the intermediacy of vinyl alcohol, which tautomerizes to acetaldehyde.
The reaction is conducted at 90–95 °C, the acetaldehyde formed is separated from water and mercury and cooled to 25–30 °C. In the wet oxidation process, iron sulfate is used to reoxidize the mercury back to the mercury salt; the resulting iron sulfate is oxidized in a separate reactor with nitric acid. Traditionally, acetaldehyde was produced by the partial dehydrogenation of ethanol: CH3CH2OH → CH3CHO + H2In this endothermic process, ethanol vapor is passed at 260–290 °C over a copper-based catalyst; the process was once attractive because of the value of the hydrogen coproduct, but in modern times is not economically viable. The hydroformylation of methanol with catalysts like cobalt, nickel, or iron salts produces acetaldehyde, although this process is of no industrial importance. Noncompetitive, acetaldehyde arises from synthesis gas with modest selectivity. Like many other carbonyl compounds, acetaldehyde tautomerizes to give an enol: CH3CH=O ⇌ CH2=CHOH ∆H298,g = +42.7 kJ/molThe equilibrium constant is 6×10−7 at room temperature, thus that the relative amount of the enol form in a sample of acetaldehyde is small.
At room temperature, acetaldehyde is more stable than vinyl alcohol by 42.7 kJ/mol: Overall the keto-enol tautomerization occurs but is catalyzed by acids. Photo-induced keto-enol tautomerization is viable under stratospheric conditions; this photo-tautomerization is relevant to the earth's atmosphere, because vinyl alcohol is thought to be a precursor to carboxylic acids in the atmosphere. Acetaldehyde is a common electrophile in organic synthesis. In condensation reactions, acetaldehyde is prochiral, it is used as a source of the "CH3C+H" synthon in aldol and related condensation reactions. Grignard reagents and organolithium compounds react with MeCHO to give hydroxyethyl derivatives. In one of the more spectacular condensation reactions, three equivalents of formaldehyde add to MeCHO to give pentaerythritol, C4. In a Strecker reaction, acetaldehyde condenses with cyanide and ammonia to give, after hydrolysis, the amino acid alanine. Acetaldehyde can condense with amines to yield imines; these imines can be used to direct subsequent reactions like an aldol condensation.
It is a building block in the synthesis of heterocyclic compounds. In one example, it converts, to 5-ethyl-2-methylpyridine. Three molecules of acetaldehyde condense to form "paraldehyde", a cyclic trimer containing C-O single bonds. Condensation of four molecules of acetaldehyde give the cyclic molecule metaldehyde. Paraldehyde can be produced in good yields. Metaldehyde is only obtained in a few percent yield and with cooling using HBr rather than H2SO4 as the catalyst. At -40 °C in the presence of acid catalysts, polyacetaldehyde is produced. Acetaldehyde forms a stable acetal upon reaction with ethanol under conditions that favor dehydration; the product, CH3CH2, is formally named 1,1-diethoxyethane but is referred to as "acetal". This can cause confusion as "acetal" is more used to describe compounds with the functional groups RCH2 or RR'C2 rather than referring to
Adolph Strecker was a German chemist, remembered for his work with amino acids. Strecker was born in Darmstadt, the son of Ludwig Strecker, an archivist working for the hessian Grand Duke. Adolph Strecker attended school in Darmstadt until 1838. After receiving his abitur in 1840, Strecker began studying science at the University of Gießen, where Justus Liebig was a professor. In August 1842, Strecker began teaching at a realschule in Darmstadt, he refused one offer to work for Liebig, but in 1846 he accepted another and became Liebig's private assistant at the University of Gießen. Strecker became a lecturer at the university. Strecker investigated a wide variety of problems in both organic and inorganic chemistry during his time at Gießen. Examples include the molecular masses of silver and carbon, the reactions of lactic acid, the decomposition of hippuric acid by nitric acid, the separation of cobalt and nickel. Strecker wanted to leave Gießen for a position at the University of Berlin, but when he heard of an open position at Norway's University of Christiania, he applied for it and in 1851 became a professor there.
While in Norway, Strecker focused on organic chemistry, covering a broad range of topics from organometallic chemistry to natural products. While in Norway, Strecker returned to Germany for several holidays. During one such visit to Darmstadt, he married on July 3, 1852, his wife died on October 13, 1853. Strecker left Norway on Christian Gottlob Gmelin's death in 1860 to accept the latter's position at the University of Tübingen. There he conducted research on guanine, xanthine and theobromine, on the toxic thallium oxides, which damaged his health severely, he moved to the University of Würzburg in 1870, but his first semester was interrupted by the Franco-Prussian War of 1870–1871. Strecker became an officer during the war and returned to the university after it, where he started his last semester. In the summer of 1871 he undertook a recreational holiday in Berchtesgaden, but his health began to deteriorate. Strecker died in Würzburg. Regnault-Strecker's kurzes Lehrbuch der Chemie. Vieweg, Braunschweig 1851 Digital edition by the University and State Library Düsseldorf 2.
Organische Chemie. 1853 1. Anorganische Chemie. 3. Verb. Aufl. 1855 2. Organische Chemie. 2. Aufl.1857 1. Anorganische Chemie. 4. Aufl.1858 1. Anorganische Chemie. 9. Neu bearb. Aufl. / von Johannes Wislicenus. 1877 The Strecker synthesis of amino acids involves the reaction of potassium cyanide, ammonium chloride, an aldehyde to make an alpha amino acid. The reaction can be run with ammonia, hydrogen cyanide, an aldehyde; because of the relative simplicity of the reactants, the Strecker synthesis has been invoked by those studying both the origin of life and meteoritic amino acids. Named for Strecker are the Strecker degradation, which involves the conversion of amino acids into imines and into ketones, the Strecker sulfite alkylation. Adolph Strecker obituary by Rudolf Wagner from Berichte der Deutschen Chemischen Gesellschaft, 1872, part V, pp. 125–131 Obituary in the Journal of the Chemical Society, 1872, volume 25, p. 353 Adolph Strecker by B. Lepsius, Allgemeine Deutsche Biographie, volume 36, Leipzig: Duncker & Humblot – entry for Strecker Adolph Strecker – brief biography and two pictures at Tübingen University
The Hell–Volhard–Zelinsky halogenation reaction halogenates carboxylic acids at the α carbon. The reaction is named after three chemists, the German chemists Carl Magnus von Hell and Jacob Volhard and the Russian chemist Nikolay Zelinsky. An example of the Hell–Volhard–Zelinsky reaction being used in practice can be seen in the preparation of alanine. An approach using a Strecker synthesis was described as "excellent but tedious" and so an alternative starting with propionic acid was developed. In its first step, a combination of bromine and phosphorous tribromide is used to prepare 2-bromopropanoic acid, converted to a racemic mixture of the amino acid product by ammonolysis. Unlike other halogenation reactions, this reaction takes place in the absence of a halogen carrier; the reaction is initiated by addition of a catalytic amount of PBr3, after which one molar equivalent of Br2 is added. PBr3 replaces the carboxylic OH with a bromide; the acyl bromide can tautomerize to an enol, which will react with the Br2 to brominate a second time at the α position.
In neutral to acidic aqueous solution, hydrolysis of the α-bromo acyl bromide occurs spontaneously, yielding the α-bromo carboxylic acid in an example of a nucleophilic acyl substitution. If an aqueous solution is desirable, a full molar equivalent of PBr3 must be used as the catalytic chain is disrupted. If little nucleophilic solvent is present, reaction of the α-bromo acyl bromide with the carboxylic acid yields the α-bromo carboxylic acid product and regenerates the acyl bromide intermediate. In practice a molar equivalent of PBr3 is used anyway to overcome the slow reaction kinetics; the mechanism for the exchange between an alkanoyl bromide and a carboxylic acid is below. The α-bromoalkanoyl bromide has a electrophilic carbonyl carbon because of the electron-withdrawing effects of the two bromides. Reformatsky reaction
Ammonium chloride is an inorganic compound with the formula NH4Cl and a white crystalline salt, soluble in water. Solutions of ammonium chloride are mildly acidic. Sal ammoniac is a name of the mineralogical form of ammonium chloride; the mineral is formed on burning coal dumps from condensation of coal-derived gases. It is found around some types of volcanic vents, it is used as fertilizer and a flavouring agent in some types of liquorice. It is the product from the reaction of hydrochloric ammonia, it is a product of the Solvay process used to produce sodium carbonate: CO2 + 2 NH3 + 2 NaCl + H2O → 2 NH4Cl + Na2CO3In addition to being the principal method for the manufacture of ammonium chloride, that method is used to minimize ammonia release in some industrial operations. Ammonium chloride is prepared commercially by combining ammonia with either hydrogen chloride or hydrochloric acid: NH3 + HCl → NH4ClAmmonium chloride occurs in volcanic regions, forming on volcanic rocks near fume-releasing vents.
The crystals deposit directly from the gaseous state and tend to be short-lived, as they dissolve in water. Ammonium chloride appears to sublime upon heating but decomposes into ammonia and hydrogen chloride gas. NH4Cl → NH3 + HClAmmonium chloride reacts with a strong base, like sodium hydroxide, to release ammonia gas: NH4Cl + NaOH → NH3 + NaCl + H2OSimilarly, ammonium chloride reacts with alkali metal carbonates at elevated temperatures, giving ammonia and alkali metal chloride: 2 NH4Cl + Na2CO3 → 2 NaCl + CO2 + H2O + 2 NH3A 5% by weight solution of ammonium chloride in water has a pH in the range 4.6 to 6.0. Some of ammonium chloride's reactions with other chemicals are endothermic like its reaction with barium hydroxide and its dissolving in water; the dominant application of ammonium chloride is as a nitrogen source in fertilizers such as chloroammonium phosphate. The main crops fertilized this way are wheat in Asia. Ammonium chloride was used in pyrotechnics in the 18th century but was superseded by safer and less hygroscopic chemicals.
Its purpose was to provide a chlorine donor to enhance the green and blue colours from copper ions in the flame. It had a secondary use to provide white smoke, but its ready double decomposition reaction with potassium chlorate producing the unstable ammonium chlorate made its use suspect. Ammonium chloride galvanized or soldered, it works as a flux by cleaning the surface of workpieces by reacting with the metal oxides at the surface to form a volatile metal chloride. For that purpose, it is sold in blocks at hardware stores for use in cleaning the tip of a soldering iron, it can be included in solder as flux. Ammonium chloride is used as an expectorant in cough medicine, its expectorant action is caused by irritative action on the bronchial mucosa, which causes the production of excess respiratory tract fluid, easier to cough up. Ammonium salts may induce nausea and vomiting. Ammonium chloride is used as a systemic acidifying agent in treatment of severe metabolic alkalosis, in oral acid loading test to diagnose distal renal tubular acidosis, to maintain the urine at an acid pH in the treatment of some urinary-tract disorders.
Ammonium chloride, under the name sal ammoniac or salmiak is used as food additive under the E number E510, working as a yeast nutrient in breadmaking and as an acidifier. It is a feed supplement for cattle and an ingredient in nutritive media for yeasts and many microorganisms. Ammonium chloride is used to spice up dark sweets called salmiak, in baking to give cookies a crisp texture, in the liquor Salmiakki Koskenkorva for flavouring. In Iran, India and Arab countries it is called "Noshader" and is used to improve the crispness of snacks such as samosas and jalebi. Ammonium chloride has been used to produce low temperatures in cooling baths. Ammonium chloride solutions with ammonia are used as buffer solutions including ACK lysis buffer. In paleontology, ammonium chloride vapor is deposited on fossils, where the substance forms a brilliant white removed and harmless and inert layer of tiny crystals; that covers up any coloration the fossil may have, if lighted at an angle enhances contrast in photographic documentation of three-dimensional specimens.
The same technique is applied in archaeology to eliminate reflection on glass and similar specimens for photography. In organic synthesis saturated NH4Cl solution is used to quench reaction mixtures. Giant squid and some other large squid species maintain neutral buoyancy in seawater through an ammonium chloride solution, found throughout their bodies and is less dense than seawater; this differs from the method of flotation used by most fish, which involves a gas-filled swim bladder. The solution tastes somewhat like salmiakki and makes giant squid unattractive for general human consumption. Ammonium chloride is used in a ~5% aqueous solution to work on oil wells with clay swelling problems, it is used as electrolyte in zinc–carbon batteries. Other uses include in hair shampoo, in the glue that bonds plywood, in cleaning products. In hair shampoo, it is used as a thickening agent in ammonium-based surfactant systems such as ammonium lauryl sulfate. Ammonium chloride is used in the textile and leather industry, in dyeing, textile printing and cotton clustering.
Around the turn of the 20th Century, Ammonium Chloride was used in aqueous solution as the electrolyte in