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?

Draw an electron-pushing mechanism for the S_N1 reaction shown below.

Provide an electron-pushing mechanism for the S_N1 reaction shown below.

Draw a plausible mechanism for the S _N1 reaction shown below.

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.

Draw a suitable mechanism for the following S _N1 reaction.

Sort the following in order of decreasing S_N1 reaction reactivity:

The two reactions given below are classified as S_N1 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.

Which of the following bromoalkanes would react more readily in an S_N1 reaction?

Benzyl iodide can either react via S_N2 or S_N1 substitution mechanism. Since Benzyl iodide is a 1* alkyl halide it is expected to react via S_N2 and not S_N1.

Draw the mechanism for the S_N1 substitution reaction and determine how this primary halide undergoes S_N1 reactions.

Identify which member of the given pairs will undergo a faster S_N1 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 S_N1 mechanism for the following solvolysis reaction.

2-bromo-2-methylbutane + ethanol ⇋ 2-ethoxy-2-methylbutane + HBr

Draw an S_N1 mechanism for the solvolysis of 2-iodo-3-methylpentane in ethanol resulting in an unrearranged product.

Propose an S_N1 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 S_N1 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 S_N1 mechanism for the following reaction involving silver-promoted rearrangement.

Predict the products for the solvolysis of the following compounds in ethanol.

Show the products expected from the S_N1 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.

Write a plausible mechanism to account for the formation of these products.

Theoretically, we expect complete racemic products through S_N1 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.

(S)-but-3-en-2-ol loses its optical activity when placed in an acidic solution. Write a mechanism for the racemization reaction.