10. Addition Reactions

Would you expect but-2-ene or 2-methylbut-2-ene to react more quickly with HBr?

If you react carvone with a single equivalent of HBr, only one product is produced, even though carvone has two carbon–carbon double bonds. Explain this observation.

The reaction of (E)-3-chlorohex-3-ene with HCl results in the selective formation of 3,3-dichlorohexane instead of 3,4-dichlorohexane. Explain this result.

Predict the product(s) that would result when the alkenes shown here are allowed to react under the following conditions: (i) HBr;

(b)

Predict the product(s) that would result when the alkenes shown here are allowed to react under the following conditions:(ii) HCl;

(b)

Predict the product(s) that would result when the alkenes shown here are allowed to react under the following conditions: (i) HBr

(g)

Predict the product(s) that would result when the alkenes shown here are allowed to react under the following conditions:(ii) HCl

(g)

Predict the product(s) that would result when the alkenes shown here are allowed to react under the following conditions: (i) HBr

(k)

Predict the product(s) that would result when the alkenes shown here are allowed to react under the following conditions:(ii) HCl

(k)

Imagine an electrophilic addition where the first step is exothermic. Which carbocation—2°, 3°, or neither—would you expect to form preferentially? Explain.

At the beginning of Chapter 9, we stated that after finishing Chapters 8 and 9, we would have the ability to make a large variety of functional groups using related reactions. Show the reagent(s) necessary to convert 1-isobutylcyclohexene into the following molecules.

(a)

Specify the conditions that would allow the synthesis of the 1° and 3° bromoalkanes from the same starting alkene.

The following haloalkanes can all be prepared starting from the same alkene. Give the alkene and the reagents needed for each.

Predict the product and provide a mechanism for the reaction of 1-methylcyclohexene with HBr.

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Provide a mechanism for the following reactions occurring with rearrangement.

(b)