acetyl chloride acetyl chloride acetyl chloride (ch3cocl) is an acyl chloride derived from acetic acid (ch3cooh). it belongs to the class of organic compounds called acid halides. it is a colorless, corrosive, volatile liquid. its formula is commonly abbreviated to accl. acetyl chloride skeletal formula of acetyl chloride ball-and-stick model of acetyl chloride names preferred iupac name acetyl chloride systematic iupac name ethanoyl chloride other names acyl chloride identifiers cas number 75-36-5 y 3d model (jsmol) interactive image beilstein reference 605303 chebi chebi:37580 y chemspider 6127 y echa infocard 100.000.787 ec number 200-865-6 gmelin reference 1611 pubchem cid 6367 rtecs number ao6390000 unii qd15rno45k y un number 1717 comptox dashboard (epa) dtxsid2023852 inchi inchi=1s/c2h3clo/c1-2(3)4/h1h3 ykey: wetwjcdkmrhupv-uhfffaoysa-n yinchi=1/c2h3clo/c1-2(3)4/h1h3key: wetwjcdkmrhupv-uhfffaoyaq smiles clc(=o)c properties chemical formula ch3cocl molar mass 78.49 g/mol appearance colorless liquid density 1.104 g/ml, liquid melting point −112 °c (−170 °f; 161 k) boiling point 52 °c (126 °f; 325 k) solubility in water reacts with water magnetic susceptibility (χ) -38.9·10−6 cm3/mol structure dipole moment 2.45 d hazards ghs labelling: pictograms signal word danger hazard statements h225, h302, h314, h335, h412 precautionary statements p210, p233, p240, p241, p242, p243, p260, p261, p264, p270, p271, p273, p280, p301+p312, p301+p330+p331, p303+p361+p353, p304+p340, p305+p351+p338, p310, p312, p321, p330, p363, p370+p378, p403+p233, p403+p235, p405, p501 nfpa 704 (fire diamond) 3 3 2w flash point 4 °c (39 °f; 277 k) autoignitiontemperature 390 °c (734 °f; 663 k) explosive limits 7.3–19% related compounds related acyl chlorides propionyl chloridebutyryl chloride related compounds acetic acidacetic anhydrideacetyl bromide except where otherwise noted, data are given for materials in their standard state (at 25 °c , 100 kpa). y verify (what is yn ?) infobox references not to be confused with chloroacetic acid, chloroacetyl chloride, acetylcholine, or actinium(iii) chloride. synthesis on an industrial scale, the reaction of acetic anhydride with hydrogen chloride produces a mixture of acetyl chloride and acetic acid: ( ch 3 co ) 2 o + hcl ⟶ ch 3 cocl + ch 3 co 2 h laboratory routes acetyl chloride was first prepared in 1852 by french chemist charles gerhardt by treating potassium acetate with phosphoryl chloride. acetyl chloride is produced in the laboratory by the reaction of acetic acid with chlorodehydrating agents such as phosphorus trichloride (pcl3), phosphorus pentachloride (pcl5), sulfuryl chloride (so2cl2), phosgene, or thionyl chloride (socl2). however, these methods usually give acetyl chloride contaminated by phosphorus or sulfur impurities, which may interfere with the organic reactions. other methods when heated, a mixture of dichloroacetyl chloride and acetic acid gives acetyl chloride. it can also be synthesized from the catalytic carbonylation of methyl chloride. it also arises from the reaction of acetic acid, acetonitrile, and hydrogen chloride. occurrence acetyl chloride is not expected to exist in nature, because contact with water would hydrolyze it into acetic acid and hydrogen chloride. in fact, if handled in open air it releases white "smoke" resulting from hydrolysis due to the moisture in the air. the smoke is actually small droplets of hydrochloric acid and acetic acid formed by hydrolysis. uses acetyl chloride is used for acetylation reactions, i.e., the introduction of an acetyl group. acetyl 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. two major classes of acetylations include esterification and the friedel-crafts reaction. acetic acid esters and amide acetyl chloride is a reagent for the preparation of esters and amides of acetic acid, used in the derivatization of alcohols and amines. one class of acetylation reactions are esterification, for example the reaction with ethanol to produce ethyl acetate and hydrogen chloride: ch 3 cocl + ho − ch 2 − ch 3 ⟶ ch 3 − coo − ch 2 − ch 3 + hcl frequently such acylations are carried out in the presence of a base such as pyridine, triethylamine, or dmap, which act as catalysts to help promote the reaction and as bases neutralize the resulting hcl. such reactions will often proceed via ketene. friedel-crafts acetylations a second major class of acetylation reactions are the friedel-crafts reactions.