An aldehyde is a class of organic compounds characterized by the presence of a carbonyl group (a carbon atom double-bonded to an oxygen atom) bonded to a hydrogen atom and another organic group. They are often distinguished by their distinct, sometimes pungent, odor. Aldehydes play essential roles in organic chemistry, serving as key intermediates in various chemical reactions and synthesis processes. They are also found naturally in many essential oils and flavors, contributing to the characteristic scents and tastes of numerous fruits, flowers, and spices. Common aldehydes include formaldehyde (used as a preservative and in manufacturing), acetaldehyde (found in alcoholic beverages and responsible for some hangover effects), and benzaldehyde (providing the almond-like aroma in some foods and perfumes).
Acid chlorides, alkyl chlorides and chloroformates, alcohols, diols and polyols, aldehydes, acetals and ketones, amines, amino alcohols, heterocyclic compounds.