| IUPAC name
| Preferred IUPAC name
| Systematic IUPAC name
| Other names
Acetic acid chloride
|Molar mass||78.49 g/mol|
|Appearance||Colorless fuming liquid|
|Melting point||−112 °C (−170 °F; 161 K)|
|Boiling point||52 °C (126 °F; 325 K)|
|Solubility||Miscible with glacial acetic acid, acetone, benzene, chloroform, diethyl ether, petroleum ether|
|Vapor pressure||287 mm Hg (25 °C)|
|Safety data sheet||Sigma-Aldrich|
|Flash point||4 °C|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Acetyl chloride is an organic compound, an acyl chloride derived from acetic acid. It has the formula CH3COCl.
Acetyl chloride will react with alcohols to yield esters and hydrogen chloride:
- CH3COCl + CH2CH3OH → CH3-COO-CH2-CH3 + HCl
Acetyl chloride is a colorless fuming liquid, with a strong pungent sharp odor. It reacts with water, but is soluble in many organic solvents.
Acetyl chloride is sold by chemical suppliers. However, due to its hazards, it is difficult to acquire.
In some countries its sale is regulated as it can be used to make acetic anhydride, which is used for the manufacture of heroin.
Acetyl chloride can be prepared through several ways.
An accessible route involves the reaction of glacial acetic acid and HCl. Dried HCl gas is bubbled through glacial acetic acid. The resulting product is fractionally distilled and the fraction with a close boiling point is collected and further purified. SM member Magpie was able to obtain crude acetyl chloride with a yield of 70% using this method.
Using acetic anhydride gives a better yield, though if you need acetyl chloride for making the acetic anhydride, this route is not useful.
Reacting acetic acid with chlorinating agents, such as phosgene, phosphorus trichloride, phosphorus pentachloride, thionyl chloride, will also yield acetyl chloride. This is the most convenient route used in the lab, but these compounds are difficult to obtain and are sensitive to water, making this route expensive.
One patent claims that one of the products from the hydrolysis of chloroform in the presence of iron(III) chloride, at temperatures between 150 - 160 °C is acetyl chloride. The process takes place at low pressure.
- Make acetic anhydride
- Make esters
Acetyl chloride reacts with moisture to release fumes of hydrogen chloride and acetic acid. These fumes are very corrosive. Proper protection should be worn when handling the compound.
Acetyl chloride should be stored in air-tight containers in cool and well ventilated places. Schlenk flasks can also be used to store the compound.
Acetyl chloride can be neutralized by slowly and carefully dissolving it in a basic solution, then poured down the drain once fully neutralized.
- I.G. Farbenind.; Landolt-Boernstein E II 1651
- Mansueto, Edward S.; Wight, Charles A.; Journal of Physical Chemistry; vol. 96; nb. 3; (1992); p. 1502 - 1504