Let's solve each reaction stepwise, with explanations: --- ## (c) Addition of HCl to an Alkene **Step 1**: Identify the reaction as a **Markovnikov addition** of HCl to an alkene. - The double bond will react with HCl. - The H will add to the carbon with more hydrogens (least substituted). - The Cl will add to the more substituted carbon. **Step 2**: Draw the product: - The double bond is between the second and third carbon. - H adds to the terminal carbon, and Cl adds to the middle one. **Major Product:** 2-chloro-2-methylbutane ``` CH3 | CH3—C—CH2—CH3 | Cl ``` --- ## (d) Hydroboration-Oxidation **Step 1**: This is an **anti-Markovnikov** addition of water across the double bond (BH₃/THF, then H₂O₂/NaOH). - The OH group will attach to the less substituted carbon. **Step 2**: - Starting with 1-propyl-propene, the OH adds to the terminal carbon. - Syn addition (same side), but since the group is on a terminal carbon, stereochemistry is not relevant. **Major Product:** 1-propylpropan-1-ol (or, more simply, 1-pentanol) --- ## (e) Catalytic Hydrogenation (H₂/Pt) **Step 1**: This is a **syn addition** of H₂ to a cyclohexene ring. - All double bonds will be reduced (alkene to alkane). **Step 2**: - The product is a fully saturated ring (cyclohexane), with the isopropyl substituent intact. **Major Product:** Isopropylcyclohexane --- ## (f) Hydrogenation with Wilkinson’s Catalyst **Step 1**: Wilkinson’s catalyst selectively hydrogenates alkenes, not cyclopropanes. - Only the alkene gets reduced. **Step 2**: - The ring system retains the cyclopropyl group; only the double bond is reduced. **Major Product:** Cyclohexyl group with cyclopropyl and ethyl substituents (no double bonds). --- ## (g) Addition of Br₂ to an Alkene **Step 1**: Br₂ adds **anti** across the double bond (vicinal dibromide formation). - Stereochemistry: Br atoms add on opposite sides (trans). **Step 2**: - The cyclohexene ring will have two Br’s on adjacent carbons, trans to each other. **Major Product:** Trans-1,2-dibromocyclohexane (with the ethyl group on C1 or C2, depending on numbering). --- # **Summary Table** | Reaction | Major Product | Stereochemistry | |----------|--------------|-----------------| | (c) | 2-chloro-2-methylbutane | — | | (d) | 1-pentanol (anti-Markovnikov) | — | | (e) | isopropylcyclohexane | — | | (f) | cyclohexylcyclopropane (alkane) | — | | (g) | trans-1,2-dibromocyclohexane | trans/anti | Let me know if you need structures or further clarification!