2,2,2-Tribromoethanol, often called just tribromoethanol, is a

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 ...

with

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 ...

. Its molecule can be described as that of

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 ...

, with the three

hydrogen Hydrogen is a chemical element; it has chemical symbol, symbol H and atomic number 1. It is the lightest and abundance of the chemical elements, most abundant chemical element in the universe, constituting about 75% of all baryon, normal matter ...

atoms in position 2 (on the

methyl group In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula (whereas normal methane has the formula ). In formulas, the group is often abbreviated a ...

) replaced by

bromine Bromine is a chemical element; it has chemical symbol, symbol Br and atomic number 35. It is a volatile red-brown liquid at room temperature that evaporates readily to form a similarly coloured vapour. Its properties are intermediate between th ...

. It is a white crystalline solid, soluble in water and other solvents, that absorbs strongly in the UV below 290 nm. Tribromoethanol is used in

medicine Medicine is the science and Praxis (process), practice of caring for patients, managing the Medical diagnosis, diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, ...

and

biology Biology is the scientific study of life and living organisms. It is a broad natural science that encompasses a wide range of fields and unifying principles that explain the structure, function, growth, History of life, origin, evolution, and ...

as an

anesthetic An anesthetic (American English) or anaesthetic (British English; see spelling differences) is a drug used to induce anesthesia ⁠— ⁠in other words, to result in a temporary loss of sensation or awareness. They may be divided into t ...

, and has been available commercially for that purpose by the trade name Avertin. It was formerly used on humans and is still often used on laboratory animals, and to capture wild birds. It is also used in

plastic Plastics are a wide range of synthetic polymers, synthetic or Semisynthesis, semisynthetic materials composed primarily of Polymer, polymers. Their defining characteristic, Plasticity (physics), plasticity, allows them to be Injection moulding ...

s industry as a

polymerization In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are many fo ...

initiator An initiator can refer to: * A person who instigates something. * Modulated neutron initiator, a neutron source used in some nuclear weapons ** Initiator, an Explosive booster ** Initiator, the first Nuclear chain reaction * Pyrotechnic initiator, ...

Uses

Animal anesthetic

Tribromoethanol is often used to anesthetize laboratory animals, particularly rodents, before surgery. As a solution in ''tert''-amyl alcohol, it has the brand name Avertin. The ''tert''-amyl alcohol acts as a weak

hypnotic A hypnotic (from Ancient Greek, Greek ''Hypnos'', sleep), also known as a somnifacient or soporific, and commonly known as sleeping pills, are a class of psychoactive drugs whose primary function is to sleep induction, induce sleep and to trea ...

, in addition to improving the solubility of the tribromoethanol. Administered intravenously, tribromoethanol (Avertin) causes rapid and deep anesthesia followed by rapid and full postoperative recovery in small mammals. Recently its safety for this purpose has been questioned.Robert E. Meyer and Richard E. Fish (2005) "A review of tribromoethanol anesthesia for production of genetically engineered mice and rats". ''Lab Animal'', volume 34, pages 47–52.

Wildlife capture

Tribromoethanol has also been long used as spiked grain bait to capture

wild turkey The wild turkey (''Meleagris gallopavo'') is an upland game bird native to North America, one of two extant species of Turkey (bird), turkey and the heaviest member of the order Galliformes. It is the ancestor to the domestic turkey (''M. g. dom ...

s for research and wildlife management purposes. However, the birds learn to avoid it, for over a year, after a single exposure, and will drive other flock members away from the bait when they detect it.

Human anesthetic

In the first half of the 20th century, Avertin was also used in humans as a general anesthetic or basal narcotic to induce unconsciousness prior to the administration of other anesthetic agents. It was administered rectally as a retention

enema An enema, also known as a clyster, is the rectal administration of a fluid by injection into the Large intestine, lower bowel via the anus.Cullingworth, ''A Manual of Nursing, Medical and Surgical'':155 The word ''enema'' can also refer to the ...

or by intravenous injection. Its rectal use was particularly favored for pediatrics, head or neck surgery, or in mentally unstable or anxious patients.

Electrophysiology Electrophysiology (from ee the Electron#Etymology, etymology of "electron" ; and ) is the branch of physiology that studies the electrical properties of biological cell (biology), cells and tissues. It involves measurements of voltage change ...

studies showed that tribromoethanol acts as a

positive allosteric modulator In pharmacology and biochemistry, allosteric modulators are a group of substances that bind to a receptor to change that receptor's response to stimuli. Some of them, like benzodiazepines or alcohol, function as psychoactive drugs. The site that ...

of the inhibitory GABA_A and glycine receptors, a mechanism similar to that seen with the related compound 2,2,2-trichloroethanol. Bromal hydrate (2,2,2-tribromoethanol-1,1-diol), a compound also recognized to produce general anesthesia in animals, is metabolized to tribromoethanol.

Polymerization initiator

Tribromoethanol can be used as a functional polymerization initiator for the introduction of α-

hydroxyl In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy ...

groups in

poly(methyl methacrylate) Poly(methyl methacrylate) (PMMA) is a synthetic polymer derived from methyl methacrylate. It is a transparent thermoplastic, used as an engineering plastic. PMMA is also known as acrylic, acrylic glass, as well as by the trade names and bran ...

(PMMA) and poly(n-butyl acrylate) (PBAK).

Chemistry

Photolysis

Tribromoethanol should be kept refrigerated and in the dark, to prevent decomposition by light into

hydrobromic acid Hydrobromic acid is an aqueous solution of hydrogen bromide. It is a strong acid formed by dissolving the diatomic molecule hydrogen bromide (HBr) in water. "Constant boiling" hydrobromic acid is an aqueous solution that distills at and contains ...

and possibly 2,2-dibromoacetaldehyde or

glycolic acid Glycolic acid (or hydroxyacetic acid; chemical formula ) is a colorless, odorless and hygroscopic crystal, crystalline solid, highly solubility, soluble in water. It is used in various skin care, skin-care products. Glycolic acid is widespread in ...

References

{{Glycinergics Anesthetics Tribromomethyl compounds Primary alcohols