Show the products of the following acetylide alkylation reactions. [Make sure your product has the correct number of carbons.]
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Verified step by step guidance

1. Identify the reactants in the acetylide alkylation reaction. Acetylide ions are strong nucleophiles formed by deprotonating terminal alkynes with a strong base, such as NaNH₂. The alkyl halide provides the electrophile for the reaction.
2. Determine the structure of the acetylide ion. The acetylide ion is formed by removing the terminal hydrogen from the alkyne, leaving a negatively charged carbon triple-bonded to another carbon.
3. Analyze the alkyl halide used in the reaction. The alkyl halide should be a primary or methyl halide to avoid side reactions such as elimination. Secondary or tertiary alkyl halides are less suitable for this reaction.
4. Write the mechanism of the reaction. The acetylide ion attacks the carbon atom of the alkyl halide in an SN2 reaction, displacing the halide ion (leaving group) and forming a new carbon-carbon bond.
5. Combine the acetylide ion and the alkyl group from the alkyl halide to determine the product. Ensure the product has the correct number of carbons by adding the carbons from the acetylide ion and the alkyl halide together.

Key Concepts

Acetylide Ions

Acetylide ions are negatively charged species formed by deprotonating terminal alkynes. They are strong nucleophiles, capable of attacking electrophiles in nucleophilic substitution reactions. Understanding their formation and reactivity is crucial for predicting the products of alkylation reactions.

Alkylation Reactions

Alkylation reactions involve the transfer of an alkyl group from one molecule to another, typically through nucleophilic substitution. In the context of acetylide alkylation, the acetylide ion attacks a primary alkyl halide, resulting in the formation of a new carbon-carbon bond. This process is essential for building larger carbon skeletons in organic synthesis.

Carbon Count in Products

Maintaining the correct number of carbons in the product is vital in organic chemistry. When performing acetylide alkylation, the total number of carbon atoms in the starting materials must equal the total in the products. This concept ensures that the reaction adheres to the law of conservation of mass and helps in verifying the accuracy of the proposed products.