dioxanes

Dioxanes are a family of six‑membered heterocyclic compounds containing two oxygen atoms in the ring. The saturated ring has the formula C4H8O2, and the two oxygen atoms can occupy various positions, giving several isomers. The most common is 1,4-dioxane, followed by 1,3-dioxane and 1,2-dioxane. Among these, 1,4-dioxane is the best known and most widely used.

In terms of structure, the two oxygen atoms in the ring influence the conformation and physical properties of the molecule. The different isomers exhibit variations in reactivity and polarity, which in turn affect their applications as solvents and intermediates.

Occurrence and production: 1,4-Dioxane is produced industrially by cyclization reactions involving diols and carbonyl compounds under acidic conditions. It can also form as a trace byproduct during ethoxylation processes used to manufacture surfactants and related products. The compound is a colorless, volatile liquid that is miscible with water and many organic solvents.

Uses: Dioxanes are primarily used as solvents in the production of polymers, resins, dyes, and pharmaceuticals. 1,4-dioxane is particularly common as a polar solvent in various industrial applications. It can be found as a contaminant in products made by ethoxylation, which has led to regulatory scrutiny in some jurisdictions.

Safety and regulation: 1,4-Dioxane is regarded as a probable human carcinogen by several health agencies. It is flammable and requires appropriate handling and controls to minimize exposure and environmental release.