Hydroxialdehyde

Hydroxialdehyde is a term that can refer to two distinct types of chemical compounds, depending on the context. In organic chemistry, it most commonly refers to a molecule containing both a hydroxyl group (OH) and an aldehyde group (CHO) within its structure. These compounds exhibit the reactivity of both functional groups. For instance, a simple example is glycolaldehyde, which is the smallest of the hydroxyaldehydes. They can participate in oxidation-reduction reactions, esterification of the hydroxyl group, and nucleophilic addition reactions at the aldehyde carbonyl. Some naturally occurring hydroxialdehydes play roles in biological processes.

Alternatively, in some older or less precise chemical literature, "hydroxialdehyde" might be used as a less common synonym for a compound containing a hydroxide ion (OH-) and an aldehyde molecule. However, this interpretation is not standard in modern chemical nomenclature. The presence of a hydroxide ion typically indicates an alkaline environment or a basic compound. The combination of a hydroxide ion directly bonded to an aldehyde carbon is generally unstable and would likely deprotonate to form a hydrate or undergo other reactions. Therefore, the understanding of hydroxialdehyde as a single molecule with both a hydroxyl group and an aldehyde group is the prevailing and scientifically accurate interpretation.