Fundamentals of Organic ChemistryChemistryAlcohols Phenols and Ethers
Identify the appropriate reaction conditions for the transformations A, B, and C shown in the following scheme:
Options
- AA: Oxymercuration-demercuration; B: Acid-catalysed hydration; C: Hydroboration-oxidation
- BA: Acid-catalysed hydration; B: Hydroboration-oxidation; C: Oxymercuration-demercuration
- CA: Hydroboration-oxidation; B: Oxymercuration-demercuration; C: Acid-catalysed hydration
- DA: Oxymercuration-demercuration; B: Hydroboration-oxidation; C: Acid-catalysed hydration
Correct answer
C. A: Hydroboration-oxidation; B: Oxymercuration-demercuration; C: Acid-catalysed hydration
Step-by-step solution
The starting material is vinylcyclohexane. Transformation A yields 2-cyclohexylethanol. This is an anti-Markovnikov addition of water across the double bond, which is achieved by hydroboration-oxidation. Transformation B yields 1-cyclohexylethanol. This is a Markovnikov addition of water without any skeletal rearrangement, which is achieved by oxymercuration-demercuration. Transformation C yields 1-ethylcyclohexanol. This product is formed via a carbocation rearrangement, characteristic of acid-catalysed hydration.