91Ó°ÊÓ

An aldol addition reaction occurs between two molecules of ketone or aldehyde.A new C-C bond is formed between α -carbon of one molecule (acts as a nucleophile) and the carbon that was originally the carbonyl carbon of another molecule (acts as an electrophile).

a. An aldol addition product is formed when two aldehyde molecules are taken. A new C-C bond is formed in which the carbon bonded to OH is adjacent to the carbon attached to the CH=O group. As the reactant is an aldehyde, the product formed is ß -hydroxyaldehyde.

An aldol addition reaction (a)

b. An aldol addition product is formed when two molecules of a given ketone are added. A new C-C single bond is formed in which the carbon bonded to OH is adjacent to the carbon attached to the C=O group. As the reactant is a ketone, the product formed is ß -hydroxyketone.

An aldol addition reaction (b)

c. When two molecules of cyclohexanone(ketone) are added, an aldol addition reaction occurs. A new C-C single bond is formed in which the carbon bonded to OH is adjacent to the carbon attached to the C=O group. As the reactant is a ketone, the product formed is ß -hydroxyketone.

An aldol addition reaction (c)