Chapter 3 Practice Problems

Try these before revealing answers.

1. Hydrohalogenation: Major product of 2-methyl-2-butene + HBr? Regio/stereo and any rearrangement.
2. Hydration mechanism: Full mechanism for acid hydration of 3,3-dimethyl-1-butene → 3,3-dimethyl-2-butanol. Why Markovnikov?
3. Synthesis planning: Make 2-bromopropane from ethanol using an alkene intermediate.
4. Regiochemistry contrast: Conditions to get (a) 1-bromopropane vs (b) 2-bromopropane from propene; explain mechanisms (radical vs carbocation).
5. Halogenation stereo: Cyclopentene + Br₂ (CCl₄). Draw product with stereochemistry. Is it optically active?
6. Ozonolysis ID: C₇H₁₄ → (O₃, Zn/H₂O) → acetone + butanal. Deduce the alkene.
7. Hydration methods: Which avoids rearrangement—acid hydration or oxymercuration? Apply to 1-methylcyclopentene products.
8. Multi-step ring: Convert 1-hexene to 1,2-dibromocyclohexane (outline steps).
9. Alcohol from 3-methyl-1-butene: Route to 3-methyl-2-butanol; why not one-step?
10. Challenge: Synthesize 2-methyl-2,3-butanediol from an alkene; choose dihydroxylation to set stereochemistry.