Discuss the mechanism of acid-catalyzed hydration of alkenes to yield alcohols. Include all the steps involved, stating clearly the role of each step in the reaction pathway.

Q: Discuss the mechanism of acid-catalyzed hydration of alkenes to yield alcohols. Include all the steps involved, stating clearly the role of each step in the reaction pathway.

Introduction to Acid-Catalyzed Hydration\nAlkenes react with water in the presence of acid as a catalyst to form alcohols. This reaction follows Markovnikov's rule. The mechanism proceeds in three fundamental steps. Step-by-Step Mechanism Step 1: Protonation of alkene to form carbocation\nThe acid catalyst ($H2SO4$ or $H^+/H2O$) dissociates to provide a proton ($H^+$, which exists as a hydronium ion, $H3O^+$). The alkene acts as a nucleophile and attacks the hydronium ion to form a carbocation. $$\text{CH}3-\text{CH}=\text{CH}2 + \text{H}3\text{O}^+ \rightarrow \text{CH}3-\text{CH}^+-\text{CH}3 + \text{H}2\text{O}$$\nThis is the slowest step and hence acts as the rate-determining step of the reaction. Step 2: Nucleophilic attack of water on carbocation\nThe carbocation formed in the first step is electrophilic in nature. A water molecule, acting as a nucleophile, attacks the carbocation to form a protonated alcohol (oxonium ion). $$\text{CH}3-\text{CH}^+-\text{CH}3 + \text{H}2\text{O} \rightarrow \text{CH}3-\text{CH}(\text{OH}2^+)-\text{CH}3$$ Step 3: Deprotonation to form alcohol\nThe protonated alcohol loses a proton ($H^+$) to another water molecule to yield a neutral alcohol molecule and regenerate the hydronium ion (catalyst). $$\text{CH}3-\text{CH}(\text{OH}2^+)-\text{CH}3 + \text{H}2\text{O} \rightarrow \text{CH}3-\text{CH}(\text{OH})-\text{CH}3 + \text{H}3\text{O}^+$$ Conclusion\nThus, through these three steps, the alkene is successfully converted into a corresponding alcohol following Markovnikov's addition of water.

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Introduction to Acid-Catalyzed Hydration
Alkenes react with water in the presence of acid as a catalyst to form alcohols. This reaction follows Markovnikov's rule. The mechanism proceeds in three fundamental steps. Step-by-Step Mechanism Step 1: Protonation of alkene to form carbocation
The acid catalyst ($H2SO4$ or $H^+/H2O$) dissociates to provide a proton ($H^+$, which exists as a hydronium ion, $H3O^+$). The alkene acts as a nucleophile and attacks the hydronium ion to form a carbocation. $$	ext{CH}3-	ext{CH}=	ext{CH}2 + 	ext{H}3	ext{O}^+ ightarrow 	ext{CH}3-	ext{CH}^+-	ext{CH}3 + 	ext{H}2	ext{O}$$
This is the slowest step and hence acts as the rate-determining step of the reaction. Step 2: Nucleophilic attack of water on carbocation
The carbocation formed in the first step is electrophilic in nature. A water molecule, acting as a nucleophile, attacks the carbocation to form a protonated alcohol (oxonium ion). $$	ext{CH}3-	ext{CH}^+-	ext{CH}3 + 	ext{H}2	ext{O} ightarrow 	ext{CH}3-	ext{CH}(	ext{OH}2^+)-	ext{CH}3$$ Step 3: Deprotonation to form alcohol
The protonated alcohol loses a proton ($H^+$) to another water molecule to yield a neutral alcohol molecule and regenerate the hydronium ion (catalyst). $$	ext{CH}3-	ext{CH}(	ext{OH}2^+)-	ext{CH}3 + 	ext{H}2	ext{O} ightarrow 	ext{CH}3-	ext{CH}(	ext{OH})-	ext{CH}3 + 	ext{H}3	ext{O}^+$$ Conclusion
Thus, through these three steps, the alkene is successfully converted into a corresponding alcohol following Markovnikov's addition of water.

CBSE · Class 12 · Chemistry · Alcohols, Phenols and EthersDiscuss the mechanism of acid-catalyzed hydration of alkenes to yield alcohols. Include all the steps involved, stating clearly the role of each step in the reaction pathway.

Introduction to Acid-Catalyzed Hydration\nAlkenes react with water in the presence of acid as a catalyst to form alcohols. This reaction follows Markovnikov's rule. The mechanism proceeds in three fundamental steps.

Step-by-Step Mechanism

Step 1: Protonation of alkene to form carbocation\nThe acid catalyst ($H_2SO_4$ or $H^+/H_2O$) dissociates to provide a proton ($H^+$, which exists as a hydronium ion, $H_3O^+$). The alkene acts as a nucleophile and attacks the hydronium ion to form a carbocation.

Step 2: Nucleophilic attack of water on carbocation\nThe carbocation formed in the first step is electrophilic in nature. A water molecule, acting as a nucleophile, attacks the carbocation to form a protonated alcohol (oxonium ion).

Step 3: Deprotonation to form alcohol\nThe protonated alcohol loses a proton ($H^+$) to another water molecule to yield a neutral alcohol molecule and regenerate the hydronium ion (catalyst).

Conclusion\nThus, through these three steps, the alkene is successfully converted into a corresponding alcohol following Markovnikov's addition of water.