Acetyl chloride 1562440 216603245 2008-06-02T11:26:58Z Beetstra 855858 split, unlink {{Chembox new | Name = Acetyl chloride | ImageFileL1 = Acetyl-chloride.png | ImageSizeL1 = 100px | ImageNameL1 = Skeletal formula of acetyl chloride | ImageFileR1 = Acetyl-chloride-3D-balls.png | ImageSizeR1 = 100px | ImageNameR1 = Ball-and-stick model of acetyl chloride | ImageFile2 = Acetyl-chloride-3D-vdW.png | ImageSize2 = 120px | ImageName2 = Space-filling model of acetyl chloride | IUPACName = Ethanoyl chloride | OtherNames = Acetyl chloride | Section1 = {{Chembox Identifiers | SMILES = CC(=O)Cl | CASNo = 75-36-5 | RTECS = AO6390000 }} | Section2 = {{Chembox Properties | Formula = CH<sub>3</sub>COCl | MolarMass = 78.5 g/mol | Appearance = colorless liquid | Density = 1.11 g/ml, liquid | Solubility = Reacts | MeltingPt = &minus;112 °C | BoilingPt = 51 °C | Viscosity = }} | Section3 = {{Chembox Structure | Dipole = 2.45 [[Debye|D]] }} | Section7 = {{Chembox Hazards | ExternalMSDS = | EUClass = Flammable ('''F''')<br />Corrosive ('''C''') | RPhrases = {{R11}}, {{R14}}, {{R34}} | SPhrases = {{S1/2}}, {{S9}}, {{S16}}, {{S26}}, {{S45}} | FlashPt = 5 °C | Autoignition = 390 °C | ExploLimits = 7.3&ndash;19% }} | Section8 = {{Chembox Related | Function = [[acyl chloride]]s | OtherFunctn = [[Propionyl chloride]]<br />[[Butyryl chloride]] | OtherCpds = [[Acetic acid]]<br />[[Acetic anhydride]] }} }} '''Acetyl chloride''', also known as '''ethanoyl chloride''', is an [[acid chloride]] (also known as an [[acyl chloride]]) derived from [[acetic acid]] ([[ethanoic acid]]). It has the formula CH<sub>3</sub>COCl and it belongs to the class of [[organic compound]]s called [[acyl halide]]s. At room temperature and pressure, it is a clear colorless [[liquid]]. Acetyl chloride does not exist in nature, because contact with [[water (molecule)|water]] would hydrolyze it into acetic acid and [[hydrogen chloride]]. In fact, if handled in open air it gives of white [[smoke]] owing to the hydrolysis from the moisture in the air. The smoke is actually [[gas]]eous hydrogen chloride which forms small droplets in the air with water vapour. ==Synthesis== Acetyl chloride is [[Chemical synthesis|synthesized]] by the reaction of [[acetic acid]] (CH<sub>3</sub>COO-H) with [[thionyl chloride]] (O=SCl<sub>2</sub>) under liberation of [[sulfur dioxide]] (SO<sub>2</sub>). :CH<sub>3</sub>COO-H + O=SCl<sub>2</sub> → CH<sub>3</sub>COCl + SO<sub>2</sub> + [[Hydrogen chloride|H-Cl]] ==Uses== It is a reagent for '''[[acetylation]]''' in the [[synthesis]] or derivatization of [[chemical compound]]s. Examples of acetylation reactions include [[acylation]] processes such as [[esterification]] (see below) and the [[Friedel-Crafts reaction]]). :CH<sub>3</sub>COCl + [[Ethanol|HO-CH<sub>2</sub>-CH<sub>3</sub>]] → [[Ethyl acetate|CH<sub>3</sub>-COO-CH<sub>2</sub>-CH<sub>3</sub>]] + [[Hydrogen chloride|H-Cl]] Frequently such acylations are carried out in the presence of a base such as [[pyridine]], [[triethylamine]], or [[4-Dimethylaminopyridine|DMAP]], which as [[catalyst]]s help to promote the reaction and as [[base (chemistry)|base]]s [[neutralization|neutralize]] the resulting HCl. Acetylation is the introduction of an [[acetyl]] group via [[acylation]] using a [[reactant]] such as acetyl chloride or [[acetic anhydride]]. An acetyl group is an [[acyl]] group having the formula :-C(=O)-CH<sub>3</sub> For further information on the types of chemical reactions compounds such as acetyl chloride can undergo, see [[acyl halide]]. ==References== {{Unreferenced|date =September 2007}} <references/> ==External links== *[http://www.ilo.org/public/english/protection/safework/cis/products/icsc/dtasht/_icsc02/icsc0210.htm International Chemical Safety Card 0210] [[Category:Acyl chlorides]] [[de:Essigsäurechlorid]] [[es:Cloruro de etanoilo]] [[fr:Chlorure d'éthanoyle]] [[id:Asetil klorida]] [[it:Cloruro di acetile]] [[ja:塩化アセチル]] [[pl:Chlorek acetylu]] [[pt:Cloreto de acetila]] [[ru:Ацетилхлорид]] [[zh:乙酰氯]]