11. Radical Reactions

Draw the major product(s) of the reaction of 1-methylcyclohexene with the following reagents, disregarding stereoisomers:

3. HBr

4. HBr/peroxide

Show how you would synthesize each compound using methylenecyclopentane as your starting material.

(b)

Propose mechanisms consistent with the following reactions.

(a)

Predict the major products of the following reactions, and propose mechanisms to support your predictions.

(b)

HINT: Remember to write out complete structures, including all bonds and charges, when writing a mechanism or determining the course of a reaction.

Show how you would accomplish the following synthetic conversions.

(a) but−1−ene → 1−bromobutane

(b) but−1−ene → 2−bromobutane

Provide the expected product for the reaction of each of the following alkenes with (i) HBr and (ii) HBr, H₂O₂

(b)

Provide the expected product for the reaction of each of the following alkenes with (i) HBr and (ii) HBr, H₂O₂

(c)

Provide the expected product for the reaction of each of the following alkenes with (i) HBr and (ii) HBr, H₂O₂.

(d)

Which reagent system (HBr or HBr, H₂O₂) would you use to carry out the following transformations?

(a)

Which reagent system (HBr or HBr, H₂O₂) would you use to carry out the following transformations?

(b)

Provide an arrow-pushing mechanism that rationalizes the formation of each of the products you predicted in Assessment 8.35 (ii). Make sure your mechanism accounts for all products formed, including stereoisomers and regioisomers, where applicable.

Propose a mechanism for the reaction of pent-1-yne with HBr in the presence of peroxides. Show why anti-Markovnikov orientation results.

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.

(f)