Chloral
Encyclopedia
Chloral, also known as trichloroacetaldehyde, is the organic compound
with the formula Cl3CCHO. This aldehyde
is a colourless oily liquid that is soluble in a wide range of solvents. It reacts with water to form chloral hydrate
, a once widely used sedative
and hypnotic
substance.
of ethanol
, as reported in 1832 by Justus von Liebig
.
. For this purpose, chloral is treated with chlorobenzene
in the presence of a catalytic amount of sulfuric acid
:
This reaction was described by Othmar Zeidler
in 1874.
Chloral is also used to form chloroform
by treating it with sodium hydroxide.
Organic compound
An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of carbon-containing compounds such as carbides, carbonates, simple oxides of carbon, and cyanides, as well as the...
with the formula Cl3CCHO. This aldehyde
Aldehyde
An aldehyde is an organic compound containing a formyl group. This functional group, with the structure R-CHO, consists of a carbonyl center bonded to hydrogen and an R group....
is a colourless oily liquid that is soluble in a wide range of solvents. It reacts with water to form chloral hydrate
Chloral hydrate
Chloral hydrate is a sedative and hypnotic drug as well as a chemical reagent and precursor. The name chloral hydrate indicates that it is formed from chloral by the addition of one molecule of water. Its chemical formula is C2H3Cl3O2....
, a once widely used sedative
Sedative
A sedative or tranquilizer is a substance that induces sedation by reducing irritability or excitement....
and hypnotic
Hypnotic
Hypnotic drugs are a class of psychoactives whose primary function is to induce sleep and to be used in the treatment of insomnia and in surgical anesthesia...
substance.
Production
Chloral can be produced by chlorinationChlorination
Chlorination is the process of adding the element chlorine to water as a method of water purification to make it fit for human consumption as drinking water...
of ethanol
Ethanol
Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...
, as reported in 1832 by Justus von Liebig
Justus von Liebig
Justus von Liebig was a German chemist who made major contributions to agricultural and biological chemistry, and worked on the organization of organic chemistry. As a professor, he devised the modern laboratory-oriented teaching method, and for such innovations, he is regarded as one of the...
.
Key reactions
Aside from its tendency to hydrate, chloral is most notable as a building block in the synthesis of DDTDDT
DDT is one of the most well-known synthetic insecticides. It is a chemical with a long, unique, and controversial history....
. For this purpose, chloral is treated with chlorobenzene
Chlorobenzene
Chlorobenzene is an aromatic organic compound with the chemical formula C6H5Cl. This colorless, flammable liquid is a common solvent and a widely used intermediate in the manufacture of other chemicals.-Uses:...
in the presence of a catalytic amount of sulfuric acid
Sulfuric acid
Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...
:
- Cl3CCHO + 2 C6H5Cl → Cl3CCH(C6H4Cl)2 + H2O
This reaction was described by Othmar Zeidler
Othmar Zeidler
Othmar Zeidler was an Austrian chemist credited with the first synthesis of DDT.He was a son of the Viennese pharmacist Franz Zeidler. Othmar's brother, Franz Zeidler Jr. , also became a chemist and would collaborate with him on several projects...
in 1874.
Chloral is also used to form chloroform
Chloroform
Chloroform is an organic compound with formula CHCl3. It is one of the four chloromethanes. The colorless, sweet-smelling, dense liquid is a trihalomethane, and is considered somewhat hazardous...
by treating it with sodium hydroxide.