Questions: Determine the products formed in each reaction. If there is no reaction, label the reaction as "no reaction". xrightarrow[[2] CH3CH2 ][[1] LDA, 78°C]
Transcript text: Determine the products formed in each reaction. If there is no reaction, label the reaction as "no reaction". $\xrightarrow[{\text { [2] } \mathrm{CH}_{3} \mathrm{CH}_{2} \text { ] }}]{\text { [1] LDA, } 78^{\circ} \mathrm{C}}$
Solution
Solution Steps
Step 1: Analyze the first reaction
The first reaction involves a ketone with no alpha-hydrogens. LDA is a strong base, but without acidic alpha-hydrogens, it cannot deprotonate the ketone. Thus, there is no reaction.
Step 2: Analyze the second reaction
The second reaction has a ketone with alpha-hydrogens. LDA will deprotonate at the less substituted side, forming the kinetic enolate. Then, the enolate will react with the primary alkyl halide (ethyl iodide) in an SN2 reaction, alkylating the ketone at the less substituted alpha carbon.
Step 3: Analyze the third reaction
The third reaction shows a ketone with LDA again. Like the second reaction, LDA will deprotonate the less hindered alpha carbon.
Final Answer
First reaction: No reaction
Second reaction:
\(\boxed{\chemfig{C6CCCC(=O)CC}}\)
Third reaction:
\(\boxed{\chemfig{C6CCCC(=O)CC}}\)