Acetyl chloride

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 = CH₃COCl
MolarMass = 78.5 g/mol
Appearance = colorless liquid
Density = 1.11 g/ml, liquid
Solubility = Reacts
MeltingPt = −112 °C
BoilingPt = 51 °C
Viscosity =
Section3 = Chembox Structure
Dipole = 2.45 D
Section7 = Chembox Hazards
ExternalMSDS =
EUClass = Flammable (F)
Corrosive (C)
RPhrases = R11, R14, R34
SPhrases = S1/2, S9, S16, S26, S45
FlashPt = 5 °C
Autoignition = 390 °C
ExploLimits = 7.3–19%
Section8 = Chembox Related
Function = acyl chlorides
OtherFunctn = Propionyl chloride
Butyryl chloride
OtherCpds = Acetic acid
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 CH₃COCl and it belongs to the class of organic compounds called acyl halides. At room temperature and pressure, it is a clear colorless liquid. Acetyl chloride does not exist in nature, because contact with water would hydrolyze it into acetic acid and hydrogen chloride. In fact, if handled in open air it gives off white smoke owing to the hydrolysis from the moisture in the air. The smoke is actually gaseous hydrogen chloride which forms small droplets in the air with water vapour.

ynthesis

Acetyl chloride is synthesized by the reaction of acetic acid (CH₃COO-H) with thionyl chloride (O=SCl₂) under liberation of sulfur dioxide (SO₂).

:CH₃COO-H + O=SCl₂ → CH₃COCl + SO₂ + H-Cl

Uses

It is a reagent for acetylation in the synthesis or derivatization of chemical compounds. Examples of acetylation reactions include acylation processes such as esterification (see below) and the Friedel-Crafts reaction).

:CH₃COCl + HO-CH₂-CH₃ → CH₃-COO-CH₂-CH₃ + H-Cl

Frequently such acylations are carried out in the presence of a base such as pyridine, triethylamine, or DMAP, which as catalysts help to promote the reaction and as bases 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)-CH₃

For further information on the types of chemical reactions compounds such as acetyl chloride can undergo, see acyl halide.

References

External links

* [http://www.ilo.org/public/english/protection/safework/cis/products/icsc/dtasht/_icsc02/icsc0210.htm International Chemical Safety Card 0210]