Aldol Reaction with and Z Enolates

In the aldol reaction, the stereochemistry of the product depends on the stereochemistry of the enolate starting material. Reaction of a (Z)-enolate with an aldehyde gives a xyn-aldol product in which both the OH and the aldehyde R are on the same side of the plane of the zigzag line drawing (both are wedges in one enantiomer and both are dashes in the other enantiomer). 

Aldol Reaction with (Z)-Enolate Gives Syn Product 

On the other hand, the reaction of an ( )-enolate with an aldehyde gives the other diastereomer, an anti aldol product with one group as a wedge and the other as a dash. 

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