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Acetyl bromide is a colorless fuming liquid, with a pungent odor, combustible and turns yellow on exposure to air. It is used as an acetylating agent in the synthesis of fi ne chemicals, agrochemicals, and pharmaceuticals. It is also used as an intermediate for dyes. Acetylation, a case of acylation, is an organic synthesis process whereby the acetyl group is incorporated into a molecule by substitution for protecting -OH groups.

A colorless fuming liquid with a pungent odor. Vapors irritate eyes and mucous membranes. Corrosive to metals and tissue. Density 13.9 lb/gal.

ACETYL BROMIDE decomposes violently upon contact with water, steam, methanol or ethanol to form hydrogen bromide gas and acetic acid. Reacts vigorously with bases, both organic and inorganic. Incompatible with oxidizing agents and alcohols. Produces highly toxic fumes of bromine and carbonyl bromide when heated to decomposition [Sax, 9th ed., 1996, p. 34]. Vapor forms an explosive mixture with air [Kirk-Othmer, 3rd ed., Vol. 1, 1978, p. 162]. May react vigorously or explosively if mixed with diisopropyl ether or other ethers in the presence of trace amounts of metal salts [J. Haz. Mat., 1981, 4, 291].

Exposures to acetyl bromide cause abdominal pain, sore throat, cough, burning sensation, shortness of breath, and respiratory distress. Contact with the skin causes pain, redness, blisters, dermatitis, and skin burn, severe deep burns, loss of vision, shock or collapse. The occupational worker may show delayed symptoms and lung edema. The vapor is corrosive to the eyes, the skin, and the respiratory tract. The irritation caused by acetyl bromide may lead to chemical pneumonitis and pulmonary edema, and may cause burns to the respiratory tract. The target organs include the eyes, skin, and the mucous membranes.

Inhalation produces primary irritation of the respiratory tract; symptoms of lung damage may be delayed. Contact with liquid produces primary irritation of eyes and severe skin damage; delayed blistering is not uncommon. INGESTION: Sore throat, abdominal pain, and vomiting.

Acetyl bromide is used as an acetylating agent in the organic synthesis of other chemicals, pesticides, perfume, pharmaceuticals, and it is also used as a dye intermediate.

If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 30 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts the skin, remove contaminated clothing and wash immediately with soap and water. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility. When this chemical has been swallowed, get medical attention. Do not induce vomiting. Medical observation is recommended for 24 to 48 hours after breathing overexposure, as pulmonary edema may be delayed.

UN1716 Acetyl bromide, Hazard class: 8; Labels: 8-Corrosive material

Acetyl bromide Vapor may form explosive mixture with air. Instability increases as temperature rises, Contact with moisture, water, steam, alcohols cause a violent reaction releasing corrosive carbonyl bromide, hydrogen bromide, and bromine gases. Incompatible with organic solvents, ethers, oxidizers, and strong bases. Corrodes or attacks most metals and wood in the presence of moisture. Contact with combustibles may cause ignition

Dispose of contents and container to an approved waste disposal plant. All federal, state, and local environmental regulations must be observed. Slow addition to sodium bicarbonate solution in a glass or plastic container. Mix slowly in another container containing lots of water. It is inappropriate and possibly dangerous to the environment to dispose of chemical wasteby flushing them down the toilet or discarding them to the trash

Acetyl Bromide is used as an acetylating agent in the synthesis of fine chemicals, agrochemicals and pharmaceuticals. It is also used as an intermediate for dyes. Further, it reacts with alcohols and amines to produce acetate esters and acetamides. In addition to this, it is involved in the synthetic process of the anti-HIV agent.

Acetyl bromide can be used:
In the quantification of lignin in cell wall residues of Arabidopsis.
In the total synthesis of cinchona alkaloids named quinidine and quinine.
To prepare 9,10-diarylanthracenes and triarylmethanes by reacting with arenes and various aromatic aldehydes using ZnBr2/SiO2.
To prepare glycosyl bromides from free sugars or their peracetates.

The preparation of acetyl bromide from acetic acid and bromine in the presence of red and yellow phosphorus.
Reaction: Acetic anhydride was brominated with bromine at 80°C, and then the bromine was added between 95°C and 125°C. About 2.5h. After the addition was completed, reflux was continued for 3h and left overnight. Refined by fractional distillation.
Acetyl bromide may also be prepared by reaction between phosphorus tribromide and acetic acid:
3CH3COOH + PBr3 → 3 CH3COBr + H3PO3

Reactivity with Water: Reacts violently, forming corrosive and toxic fumes of hydrogen bromide; Reactivity with Common Materials: Attacks and corrodes wood and most metals in the presence of moisture. Flammable hydrogen gas may collect in enclosed spaces; Stability During Transport: Stable if protected from moisture; Neutralizing Agents for Acids and Caustics: Flood with water, rinse with dilute sodium bicarbonate or soda ash solution; Polymerization: Not pertinent; Inhibitor of Polymerization: Not pertinent.

Boil acetyl bromide with PBr3/Ac2O for 1hour, then distil the latter off and redistil it. Store it dry. [Burton & Degering J Am Chem Soc 62 227 1940, Beilstein 2 IV 398.] LACHRYMATORY.