klorihydriinien

Chlorohydrins are a class of organic compounds in which chlorine and hydroxyl groups are attached to adjacent carbon atoms (vicinal haloalcohols). The general structure is often represented as R-CH(OH)-CH2-Cl, where R can be hydrogen or an alkyl group. This arrangement gives rise to two characteristic functional groups in close proximity, enabling a range of subsequent transformations.

Preparation and occurrence

Chlorohydrins are commonly prepared by adding aqueous chlorine or hypochlorous acid to alkenes, a reaction known as halohydrin formation. Alternatively, they can be formed by opening epoxides with hydrogen chloride or by hydrohalogenation of alcohol-substituted alkenes. In industry, chlorohydrins are important intermediates for the production of epoxides, most notably epichlorohydrin, which is typically obtained by converting chlorohydrins under basic conditions to generate the epoxide ring.

Properties

Chlorohydrins are typically liquids or solids with varying degrees of volatility. They are generally reactive and corrosive, often hygroscopic, and usually mix with water and many organic solvents. They can hydrolyze in moisture to release hydrochloric acid, and their reactivity makes them useful intermediates in synthesis but requires careful handling.

Applications

Chlorohydrins serve as key intermediates in the manufacture of epoxy resins, glycols, and glycerol derivatives. They are precursors to glycidyl ethers and other epoxy compounds and are used in the production of plastics, surfactants, and specialty chemicals. Their versatility stems from the ease of converting the adjacent OH and Cl groups into a variety of functional products.

Safety

Chlorohydrins are typically corrosive and irritant to skin, eyes, and the respiratory tract. Handling should occur in well-ventilated areas with appropriate PPE, and strict adherence to safety and environmental regulations is required for storage and disposal.