Chloral 2626055 221695987 2008-06-25T17:47:54Z Smokefoot 698909 tidy recent edits {{Chembox new | Name = Chloral | ImageFileL1 = Chloral-2D-skeletal.png | ImageSizeL1 = 100px | ImageNameL1 = Chloral | ImageFileR1 = Chloral-3D-vdW.png | ImageSizeR1 = 120px | ImageNameR1 = Chloral | IUPACName = Trichloroethanal | Section1 = {{Chembox Identifiers | CASNo = 75-87-6 | SMILES = ClC(Cl)(Cl)C=O }} | Section2 = {{Chembox Properties | Formula = C<sub>2</sub>HCl<sub>3</sub>O | MolarMass = 147.387 g/mol | Density = 1.512 g/cm<sup>3</sup> @ 20 °C | MeltingPt = −57.5 °C | BoilingPt = 97.8 °C<!--refractive index (D) = 1.4557--> | Solubility = forms soluble [[chloral hydrate|hydrate]] | Solubility1 = miscible | Solvent1 = ethanol | Solubility2 = miscible | Solvent2 = diethyl ether | Solubility3 = miscible | Solvent3 = chloroform }} }} '''Chloral''', also known as trichloroacetaldehyde, is the [[organic compound]] with the formula Cl<sub>3</sub>CCHO. 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. ==Production== Chloral can be produced by [[halogenation|chlorination]] of [[ethanol]], as reported in 1832 by [[Justus von Liebig]]. :4 Cl<sub>2</sub> + C<sub>2</sub>H<sub>5</sub>OH + H<sub>2</sub>O → Cl<sub>3</sub>CCH(OH)<sub>2</sub> + 5 HCl More typically [[acetaldehyde]] is chlorinated in the presence of [[hydrogen chloride]]. Both methods yield chloral hydrate that is subsequently dehydrated by treatment with [[sulfuric acid]].<ref>Reinhard Jira, Erwin Kopp, Blaine C. McKusick, Gerhard Rõderer, Axel Bosch, Gerald Fleischmann "Chloroacetaldehydes" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2007. {{DOI|10.1002/14356007.a06 527.pub2}}.</ref> :Cl<sub>3</sub>CCH(OH)<sub>2</sub> <math>\overrightarrow{\leftarrow}</math> Cl<sub>3</sub>CCHO + H<sub>2</sub>O ==Key reactions== Aside from its tendency to hydrate, chloral is most notable as a building block in the synthesis of [[DDT]]. For this purpose, chloral is treated with [[chlorobenzene]] in the presence of a catalytic amount of [[sulfuric acid]]: : Cl<sub>3</sub>CCHO + 2 C<sub>6</sub>H<sub>5</sub>Cl → Cl<sub>3</sub>CCH(C<sub>6</sub>H<sub>4</sub>Cl)<sub>2</sub> + H<sub>2</sub>O This reaction was described by [[Othmar Zeidler]] in 1874.<ref>{{cite journal | title = Verbindungen von Chloral mit Brom- und Chlorbenzol | author = Othmar Zeidler | journal = Berichte der deutschen chemischen Gesellschaft | year = 1874 | volume = 7 | issue = 2 | pages = 1180–1181 | doi = 10.1002/cber.18740070278 }}</ref> ==References== <references/> [[Category:Aldehydes]] [[Category:Organochlorides]] {{organohalide-stub}} [[de:Chloral]] [[fr:Chloral]] [[nl:Chloraal]] [[ja:クロラール]] [[pl:Chloral]] [[pt:Cloral]]