Karbonüülid

Karbonüülid is a broad term encompassing organic compounds that contain a carbonyl group. A carbonyl group is a functional group consisting of a carbon atom double-bonded to an oxygen atom (C=O). This functional group is the defining characteristic of several important classes of organic compounds. The reactivity of the carbonyl group is central to the chemistry of these molecules. The polarity of the C=O bond, with the oxygen atom being more electronegative than the carbon atom, leads to a partial positive charge on the carbon atom, making it susceptible to nucleophilic attack. Conversely, the oxygen atom, with its partial negative charge and lone pairs of electrons, can act as a Lewis base.

The most common types of karbonüülid include aldehydes, ketones, carboxylic acids, esters, amides, and acid halides. Aldehydes are characterized by having the carbonyl group at the end of a carbon chain, bonded to at least one hydrogen atom. Ketones, on the other hand, have the carbonyl group within the carbon chain, bonded to two other carbon atoms. Carboxylic acids contain a carboxyl group (-COOH), which is a carbonyl group bonded to a hydroxyl group (-OH). Esters are derivatives of carboxylic acids where the hydrogen of the hydroxyl group is replaced by an alkyl or aryl group. Amides are formed when the hydroxyl group of a carboxylic acid is replaced by an amino group. Acid halides, such as acid chlorides, have a halogen atom attached to the carbonyl carbon. These compounds exhibit diverse physical and chemical properties and play vital roles in biology, industry, and everyday life.