Vicinaldiolen

Vicinaldiolen is a rarely used term that may be encountered as an alternative or informal name for vicinal diols. In standard chemical nomenclature, the preferred term is vicinal diol (or 1,2-diols), referring to compounds in which two hydroxyl groups are attached to adjacent carbon atoms. The name “vicinaldiolen” is not widely adopted in modern IUPAC usage, and its appearance typically reflects language variation or historical text rather than a distinct class of compounds.

Structural feature and examples

A vicinal diol contains two hydroxyl groups on neighboring carbons. Simple examples include ethylene glycol (1,2-ethanediol) and propylene glycol (1,2-propanediol). These molecules are highly polar, with strong hydrogen-bonding capabilities, and they are typically miscible with water. Vicinal diols serve as important intermediates in organic synthesis and as useful solvents and antifreeze components in various applications.

key reactions and chemistry

Vicinal diols can be generated by the syn dihydroxylation of alkenes (for example, osmium tetroxide-catalyzed dihydroxylation). They can also be formed by reduction of carbonyl compounds or by dihydroxylation using other reagents. A characteristic reaction of vicinal diols is cleavage by periodate (e.g., lead tetraacetate or periodic acid), which splits the C–C bond between the two hydroxyl-bearing carbons to yield carbonyl compounds. The pinacol rearrangement is another notable transformation involving vicinal diols under acidic conditions, producing ketones or aldehydes.

Applications and context

Beyond their role as building blocks in organic synthesis, vicinal diols are important in polymer chemistry, natural products, and as protective intermediates in multi-step syntheses. While “vicinaldiolen” may appear in some sources, accurate usage typically favors vicinal diol with specific designation (such as 1,2-ethanediol or 1,2-propanediol) to specify the exact structure.