Haloacetate

Haloacetate refers to compounds derived from acetic acid by substituting one or more hydrogens on the methyl group with a halogen. The term encompasses haloacetic acids of the form X-CH2-COOH, where X is a halogen (F, Cl, Br, or I). Common examples include fluoroacetic acid, monochloroacetic acid, dichloroacetic acid, and trichloroacetic acid, as well as their salts such as sodium chloroacetate, and their esters (for example methyl chloroacetate, ethyl fluoroacetate).

Preparation and structure: Haloacetates can be prepared by halogenation of acetic acid derivatives or through routes that introduce a halogen onto the alpha carbon of acetic substrates. Ester derivatives are typically formed by standard esterification or by reaction of haloacetyl halides with alcohols.

Properties: These compounds are generally polar and water-soluble, with acidity influenced by the halogen substitution. The C–X bond in haloacetates makes the compounds reactive as alkylating agents, particularly for halogen substituents such as chlorine or bromine. Haloacetate esters are commonly used as reagents in organic synthesis.

Applications and safety: Haloacetates serve as chemical intermediates in pharmaceutical and agrochemical syntheses and as building blocks for various functionalized compounds. Environmentally, haloacetic acids are notable as disinfection byproducts in water treatment. Many haloacetates and their derivatives are toxic and may pose health and environmental risks; appropriate handling, storage, and disposal are important.

See also: haloacetic acids, disinfection byproducts, alkylating agents, halogenated organic compounds.