Ammonium compound, quaternary

Quaternary ammonium compounds are widely used antiseptics and disinfectants with a low sensitizing potential. Benzalkonium chloride is used as a skin disinfectant, for disinfection of instruments, and in treatment of burns, ulcers, etc. Cosmetics, deodorants, mouthwashes, and ophthalmic preparations, including contact lens solutions, may contain benzalkonium chloride. 

Several case reports and patients series describe contact allergy to quaternary ammonium compounds (Wahlberg 1962 Huriez et al. 1965 Afzelius and Thulin 1979). In the study by Huriez et al. (1965) a series of 71 patients cethex-onium bromide was the main culprit. Cetrimonium bromide (cetrimide BP), another quaternary ammonium compound consisting of a mixture of chemicals (Cruisk-SHANK 1949), caused several cases of contact allergy (Morgan 1968). 

Documenting allergic contact dermatitis to quaternary ammonium chloride compounds is difficult, requiring meticulous attention to detail, and should be regarded as a research project in each instance. The basic difficulty resides in the fact that these compounds have an unusual distribution of irritation with occlusive 

Quaternary ammonium compounds (QUATS) have the basic structure of a nitrogen covalently bound to four alkyl or aromatic groups such as that illustrated in Fig. 9.2. QUATS function by disrupting microbial cell 

QUATS have several advantages over other sanitizers. Formulations have extended activity over a hroad pH range, possess residual activity if not rinsed away, are heat stable, and noncorrosive. In addition, activity is not compromised hy hard water or poorly prepared surfaces. At typical application levels of 200 to 400mg/L, a thorough post-application rinsing is required. 

In wineries, QUATS commonly find application in controlling mold growth on tanks, walls, floors, and in drains. Here, the formulation is sprayed onto the surface and left without rinsing. Depending on environmental conditions and the extent of mold growth, a single application may last for several weeks. 

There are a vast number of quaternary ammonium compounds or quaternaries (1). Many are naturally occurring and have been found to be cmcial in biochemical reactions necessary for sustaining life. A wide range of quaternaries are also produced synthetically and are commercially available. Over 204,000 metric tons of quaternary ammonium compounds are produced aimuaHy in the United States (2). These have many diverse appHcations. Most are eventually formulated and make their way to the marketplace to be sold in consumer products. AppHcations range from cosmetics (qv) to hair preparations (qv) to clothes softeners, sanitizers for eating utensils, and asphalt emulsions. 

Quaternary ammonium compounds are usually named as the substituted ammonium salt. The anion is Hsted last (3). Substituent names can be either common (stearyl) or lUPAC (octadecyl). If the long chain in the compound is from a natural mixture, the chain is named after that mixture, eg, taHowalkyL Prefixes such as di- and tri- are used if an alkyl group is repeated. Complex compounds usually have the substituents Hsted in alphabetical order. Some common quaternary ammonium compounds and their appHcations in patent Hterature are Hsted in Table 1. 

Compound CAS Registry Number AppHcation and function Comments Reference 

2-chloroethyltrimethyl ammonium [999-81-5] surfactant used in formulations for plant growth 9-11 

Kirk-Othmer Encyclopedia of Chemical Technology (4th Edition) 

Tertiary amines react with primary or secondary alkyl halides by an 8 2 mechanism (eq. 11.6). The products are quaternary ammonium salts, in which all four hydrogens of the ammonium ion are replaced by organic groups. For example, 

Cationic FBAs are used to brighten polyacrylonitrile fibres. The brightening of acrylic fibres is carried by the exhaust method at an acid pH, usually in the presence of sodium chlorite or bisulfite bleach. Pyrazolines produce very high whites but are unstable to bleach and therefore the quaternary benzimidazoles are the preferred class, e.g. (3.65) and (3.66). 

These substances, widely used as disinfectants, do not work effectively against tuberculosis and gram-negative bacteria. Central sterile, environmental services, patient care areas, and clinical services use quaternary compounds for general low-level disinfecting tasks. These compounds may cause contact dermatitis and nasal irritation but less irritating to hands than other types of substances. 

Choline and carnitine are present in muscle tissue at 0.02-0.06% and 0.05-0.2%, respectively (on a fresh weight basis). Choline is synthesized from serine with colamine as an intermediary product (cf. Reactions 12.24) and carnitine is obtained from lysine through -N-trimethyllysine and bu-tyrobetaine (cf. Reactions 12.25). 

The carnitine fatty acid esters, which are in equilibrium with long chain acyl-CoA molecules in living muscle tissue, are of biochemical importance. The carnitine fatty acid ester, but not the acyl-CoA ester, can traverse the inner mitochondrial membrane. After the fatty acid is oxidized within the mitochondria, carnitine is instrumental in transporting the generated acetic acid out of the mitochondria. 

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From ehloromethyl or bromomethyl aromatic compounds by heating with hexamethylenetetramine (hexamine) in aqueous alcohol or aqueous acetic acid. A quaternary ammonium compound is formed, which yields the aldehyde upon treatment with water in the presence of hexamine for example... 

The first reported synthesis of acrylonitrile [107-13-1] (qv) and polyacrylonitrile [25014-41-9] (PAN) was in 1894. The polymer received Htde attention for a number of years, until shortly before World War II, because there were no known solvents and the polymer decomposes before reaching its melting point. The first breakthrough in developing solvents for PAN occurred at I. G. Farbenindustrie where fibers made from the polymer were dissolved in aqueous solutions of quaternary ammonium compounds, such as ben2ylpyridinium chloride, or of metal salts, such as lithium bromide, sodium thiocyanate, and aluminum perchlorate. Early interest in acrylonitrile polymers (qv), however, was based primarily on its use in synthetic mbber (see Elastomers, synthetic). 

Quaternary Ammonium Compounds. These compounds (quats) have the following general formula ... 

Strong"Base. Strong base anion-exchange resins have quaternary ammonium groups, - NR OH , where R is usually CH, as the functional exchange sites (see Quaternary ammonium compounds). These resins are used most frequentiy in the hydroxide form for acidity reduction. 

Basic Extractants. Only long-chain quaternary ammonium salts, R3NCH3 X , ia which R represents Cg—0 2 groups and X nitrate or thiocyanate, are effectively used for REE separations (see Quaternary ammonium compounds). The extractant reacts with REE according to an anion-exchange reaction ... 

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