Aldol Reaction and Aldol Condensation

Abstract The aldol reaction or aldol condensation, is one of the most important C‐C bond formation reactions for aldehydes and ketones. Aldehydes and ketones can isomerize into enolates or enols under basic or acidic conditions, respectively. The enolates or enols can further add to the carbonyl group in aldehydes or ketones, giving β‐hydroxyl carbonyl compounds known as aldols. This reaction is complicated because many possible reactions can occur at the same time. In addition, the aldol products can undergo dehydration to form conjugated carbonyl molecules (α,β‐unsaturated aldehydes or ketones, in this case; the whole process is also known as aldol condensation.) The aldehydes can undergo disproportionation to give both carboxylic acid and alcohol or to form the ester under basic conditions. Furthermore, the addition of an enolate to a carbonyl group could be complicated with eitherO‐attack orC‐attack. The aldol reaction has wide application for producing the macrolide acutiphycin.