Preparation of Alcohols - Acid-Catalyzed Hydration

$$\text{R--CH=CH}_2 + \text{H}_2\text{O} \xrightarrow{\text{H}^+} \text{R--CH(OH)--CH}_3$$

Concept: Direct electrophilic addition of water across a carbon-carbon double bond catalyzed by a strong protic acid (such as dilute $$\text{H}_2\text{SO}_4$$).

Notation & Key Points:

• Regioselectivity: Follows Markovnikov's rule (the hydroxyl group ($$\text{--OH}$$) attaches to the more substituted carbon atom).
• Intermediate: Proceeds via a discrete carbocation intermediate.
• Rearrangements: Prone to carbocation rearrangements (1,2-hydride or 1,2-methyl shifts) to form a more stable carbocation before water attacks.