orthoHydroxybenzaldehyde

ortho-Hydroxybenzaldehyde, also known as salicylaldehyde, is an organic compound with the chemical formula C7H6O2. It is a colorless to pale yellow liquid with a characteristic almond-like odor. This compound is an aromatic aldehyde and a phenol, meaning it contains both an aldehyde group (-CHO) and a hydroxyl group (-OH) attached to a benzene ring. The hydroxyl group is positioned ortho to the aldehyde group, which is why it is referred to as ortho-hydroxybenzaldehyde.

Salicylaldehyde is a key intermediate in the synthesis of various chemicals, including pharmaceuticals, dyes, and fragrances. It is naturally found in the essential oils of plants like meadowsweet and wintergreen. Industrially, it is typically produced through the Reimer-Tiemann reaction, which involves the ortho-formylation of phenol using chloroform and a strong base. Another method is the oxidation of ortho-cresol.

The chemical properties of salicylaldehyde are influenced by the presence of both the aldehyde and hydroxyl groups. It can undergo reactions typical of aldehydes, such as oxidation to salicylic acid and reduction to salicyl alcohol. The phenolic hydroxyl group can participate in ether and ester formation, and it also contributes to the compound's ability to form intramolecular hydrogen bonds with the aldehyde oxygen, which affects its physical properties like boiling point and solubility. Salicylaldehyde is moderately soluble in water and soluble in many organic solvents.