SN1 Reaction Practice Problems
Explain why the bromoalkane (b) shown below participates in an S N1 reaction at a much lower rate compared to the bromoalkane (a).
Arrange the following compounds in decreasing order of their reactivity towards S N1 reactions.
Which of the following iodoalkanes would more readily undergo an S N1 reaction? Why?
Which of the following S N1 reactions would occur more readily? Draw a reaction coordinate diagram to show the relative rates of carbocation formation in both reactions.
The two reactions given below are classified as SN1 reactions. Provide the structural formulas for the products formed, and include stereochemistry in your answers.
a. 4-chloro-4-methylheptane + methanol
b. 3-bromo-3-methylheptane + methanol
For the reaction of 1-bromo-3,3-dimethylbutane with methanol, its rate increases with the addition of silver nitrate into the mixture. Explain this observation.
Benzyl iodide can either react via SN2 or SN1 substitution mechanism. Since Benzyl iodide is a 1* alkyl halide it is expected to react via SN2 and not SN1.
Draw the mechanism for the SN1 substitution reaction and determine how this primary halide undergoes SN1 reactions.
Identify which member of the given pairs will undergo a faster SN1 reaction.
a. 1-chlorobutane or 2-chlorobutane
b. 2-chloro-2-methylpropane or 2-chlorobutane
Which member among the following pairs will undergo solvolysis in ethanol faster than the other?
Draw a suitable SN1 mechanism for the following solvolysis reaction.
2-bromo-2-methylbutane + ethanol ⇋ 2-ethoxy-2-methylbutane + HBr
Draw an SN1 mechanism for the solvolysis of 2-iodo-3-methylpentane in ethanol resulting in an unrearranged product.
Propose an SN1 mechanism for the following solvolysis reaction involving a hydride shift to form a more stable carbocation intermediate.
Primary alkyl halides can be forced to undergo SN1 reactions by adding silver nitrate to the reaction. The silver ion reacts with the halogen to produce silver halide and carbocation.
R—X + Ag+ → R+ + AgX↓
Predict the SN1 mechanism for the following reaction involving silver-promoted rearrangement.
Show the products expected from the SN1 solvolysis of the following allylic halides in methanol.
(S)-3-bromobut-1-ene is optically active but loses its optical activity when it is treated with a solution of potassium bromide. Explain using a mechanism.
When 1-bromo-3-methylbut-2-ene is placed in methanol, it undergoes solvolysis to form two substitution products.
Write a mechanism to account for the formation of these two products.
Nucleophilic substitution reactions of alkyl halides are often facilitated by silver nitrate (AgNO3). When 4-chloro-2-methylpent-2-ene reacts with AgNO3 in methanol, the reaction yields two different ether products. Draw a mechanism that accounts for the formation of both ethers.
Theoretically, we expect complete racemic products through SN1 reactions but in reality, the inversion product is favored in most cases.
However, with more stable carbocations, the excess of inversion products decreases, and the highly stable carbocation gives completely racemized products. Explain the reason behind this observation.