Textbook Question
Suggest an arrow-pushing mechanism that accounts for the formation of the following products.
(a)
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10. Addition Reactions
Acid-Catalyzed Hydration
2:34 minutesProblem 61k(iv)
Textbook Question
Predict the product(s) that would result when the alkenes shown here are allowed to react under the following conditions: (iv) H2SO4 , H2O
(k) 
Verified step by step guidance1
Identify the type of reaction: The reaction involves an alkene reacting with H₂SO₄ (sulfuric acid) and H₂O (water). This is an acid-catalyzed hydration reaction, which adds a water molecule (H and OH) across the double bond of the alkene.
Determine the regioselectivity: Acid-catalyzed hydration follows Markovnikov's rule. This means the hydrogen (H⁺) from H₂SO₄ will add to the carbon of the double bond that has more hydrogens already attached, while the hydroxyl group (OH⁻) will add to the carbon with fewer hydrogens.
Propose the carbocation intermediate: After the protonation of the alkene by H⁺, a carbocation intermediate is formed. Check for the stability of the carbocation. If a more stable carbocation can be formed through rearrangement (e.g., hydride or alkyl shift), this will occur.
Add the hydroxyl group: The OH⁻ group from water will attack the carbocation, forming a new bond. This step completes the addition of water across the double bond.
Finalize the product: Deprotonation of the intermediate (loss of H⁺) will yield the final alcohol product. Ensure the product is consistent with Markovnikov's rule and check for any stereochemistry if applicable.
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2mKey Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Electrophilic Addition
Electrophilic addition is a fundamental reaction mechanism in organic chemistry where an electrophile reacts with a nucleophile, typically involving alkenes. In the presence of strong acids like H₂SO₄, the double bond of the alkene acts as a nucleophile, attacking the electrophilic hydrogen, leading to the formation of a carbocation intermediate. This step is crucial for predicting the products of reactions involving alkenes.
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Carbocation Stability
Carbocation stability is a key concept in understanding the outcomes of reactions involving alkenes. Carbocations are positively charged species that can vary in stability based on their structure; tertiary carbocations are more stable than secondary or primary ones due to hyperconjugation and inductive effects. The stability of the carbocation formed during the electrophilic addition will influence the final product of the reaction.
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Hydration Reaction
The hydration reaction refers to the addition of water (H₂O) to an alkene, resulting in the formation of an alcohol. Under acidic conditions, such as with H₂SO₄, the alkene first forms a carbocation, which then reacts with water to yield an alcohol. This process is essential for predicting the products when alkenes react with acids and water, as it determines the final structure of the alcohol formed.
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