Part A Base-Catalyzed Aldol Reactions

Devise a reasonable mechanism for the reaction in Model 1. Hint In the first step, hydroxide reacts with one molecule of aldehyde to produce a carbon nucleonhile as in Mem. Task 25.1. 

Model 2 Analysis of an Aldol Product Using Retrosynthesis 

On the aldol product above, complete Step 1 by drawing a line through the new C—C bond. 

Explain how a mixture of acetaldehyde and hydroxide is equivalent to the nucleophilic synthon. 

In what way is acetaldehyde (by itself) similar to (acts like) the electrophilic s5mthon shown above  

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