Definition

1. Noun:
   • A colorless, volatile, and corrosive organic compound with the chemical formula CH₃COCl. It is classified as an acyl chloride, specifically the acid chloride derived from acetic acid. It is characterized by its strong, pungent, and irritating odor and its vigorous, often violent, reaction with water and alcohols.

Usage Examples

• Noun:
  • The laboratory synthesis required the careful addition of acetyl chloride to the reaction mixture.
  • Acetyl chloride is a common reagent for introducing an acetyl group into other molecules, a process known as acetylation.
  • Due to its reactivity with moisture in the air, acetyl chloride must be stored and handled under anhydrous conditions.

Advanced Usage

• In Organic Synthesis: Acetyl chloride is a fundamental reagent for synthesizing esters, amides, and acid anhydrides. It acts as an acetylating agent, transferring the CH₃CO- (acetyl) group to nucleophiles like alcohols (to form esters) or amines (to form amides).
  • Example: Acetyl chloride reacts rapidly with ethanol to form ethyl acetate and hydrogen chloride gas.
• As a Laboratory Reagent: Its high reactivity makes it a standard choice for testing the presence of hydroxyl (-OH) groups in organic compounds, as the reaction often produces visible fumes of hydrogen chloride (HCl).

Variants and Related Words

• Ethanoyl chloride: This is the systematic IUPAC name for acetyl chloride.
• Acyl chloride: The general class of organic compounds to which acetyl chloride belongs (RCOCl).
• Acetic anhydride: A related, less reactive acetylating agent with the formula (CH₃CO)₂O.
• Acetylation: The chemical process of introducing an acetyl group into a compound, for which acetyl chloride is a common reagent.

Synonyms

• Ethanoyl chloride (IUPAC name)

Notes on Different Meanings

• Acetyl chloride has a very specific meaning in chemistry. It does not have common alternative definitions outside of its use as a chemical compound and reagent. Its primary significance is its role as a reactive intermediate and synthetic tool in organic chemistry.

Noun

1. colorless liquid acyl chloride (CH3COCl) that has a pungent odor