Aldol reaction

Addition of an enolate or enol to an aldehyde or ketone, giving a beta-hydroxy carbonyl compound. Subsequent dehydration is a distinct step and gives an aldol condensation.

Aldol-type carbonyl addition at a more remote carbon of a conjugated enolate.

conjugate addition generates an enolate that is intercepted by an aldehyde or ketone.

An aldol reaction between two reactive sites of the same molecule. A tethered enol or enolate attacks a carbonyl group to close a ring; the tether, conformation and competing chemical reactions influence the product.

An aldol addition organized through a boron enolate and a coordinated carbonyl partner. Enolate geometry and auxiliary-controlled facial selection jointly determine product stereochemistry.

A six-membered chair-like organization of a metal enolate and carbonyl compound used to rationalize aldol stereoselectivity.

A six-membered chair-like transition-state model for an aldol-type bond-forming step. It predicts relative stereochemistry by comparing substituent placement and nonbonded interactions, but must be adapted to the actual enamine or metal-enolate catalyst.

An enamine formed reversibly between proline and an enolizable carbonyl compound attacks an electrophilic carbonyl. The carboxylic acid group can orient and activate the electrophile; hydrolysis releases the aldol product and regenerates proline.

An aldol addition followed by water elimination, commonly producing a conjugated carbonyl compound. Identifying which carbonyl supplies the enolate distinguishes constitutional products.