7. Substitution Reactions

Would you expect the following conditions to favor S_N1 or S_N2?

(d)

For each solvent, indicate the most likely substitution reaction to take place.

(f)

Predict the product for the following substitution reactions. Indicate whether each reaction likely proceeds by an S_N1 or S_N2 mechanism.

(b)

Predict the product of the substitution reactions, paying attention to the stereochemical outcome.

(d)

Even with an excess of cyanide, only one equivalent will react with the following dibromoalkane. To which carbon will the cyanide add? Predict the product and explain your choice.

Predict the product of the following substitution reactions, paying close attention to the stereochemical outcome of the reactions.

(f)

Predict the product of the reaction

What stereoisomers do the following reactions form?

a.

Provide an arrow-pushing mechanism that rationalizes the outcome of the reaction shown.

Give a mechanism for the following substitution and elimination reactions.

(a)

For each solvent, indicate the most likely substitution reaction to take place.

(d)

Would the following nucleophiles be more likely to participate in an S_N1 or S_N2 reaction?

(b) F^-

For each solvent, indicate the most likely substitution reaction to take place.

(b)

Show how you might use S_N2 reactions to convert 1-chlorobutane into the following compounds.

b. 1-fluorobutane

Draw the substitution products for each of the following reactions; if the products can exist as stereoisomers, show what stereoisomers are obtained:

a. (R)-2-bromopentane+CH₃O⁻

b. (R)-3-bromo-3-methylheptane+CH₃OH