Chemistry · Alkyl Halides and Amines
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Which of the following solvents favor SN2 reactions?
- A
Water
- B
Ammonia
- C
Carbon tetrachloride
- D
Acetic acid
The correct answer is Carbon tetrachloride, which is a non-polar solvent that does not stabilize ions and thus allows for a more favorable environment for SN2 reactions. In SN2 mechanisms, the nucleophile attacks the substrate in a single concerted step, and polar protic solvents like water, ammonia, and acetic acid can hinder this process by stabilizing the transition state or the leaving group, making them less favorable for such reactions.
In contrast, polar aprotic solvents (like carbon tetrachloride) do not solvate the nucleophile as strongly, allowing it to remain reactive and effectively participate in the nucleophilic substitution process.
Water is a polar protic solvent that can stabilize cations but is not ideal for SN2 reactions, which prefer polar aprotic solvents that do not form strong hydrogen bonds.
Ammonia is a polar protic solvent, similar to water, and is not the best choice for SN2 reactions due to its ability to stabilize cations rather than facilitate nucleophilic attack.
Carbon tetrachloride is a non-polar solvent that does not stabilize ions. However, it can be conducive to SN2 reactions as it does not interfere with the nucleophile's attack on the substrate.
Acetic acid is a polar protic solvent that can stabilize cations and slow down the SN2 reaction process, making it less favorable for this type of reaction.
Tagged under Chemistry · Alkyl Halides and Amines · 2021