`Ph-CH_2-CH=CH_2overset(dil. H_2SO_4)rarrA,A` is

Options

A. `Ph-CH_2-CH_2-CH_2-OH`
B. `Ph-CH_2-underset(OH)underset(|)(CH)-CH_3`
C. `Ph-underset(OH)underset(|)(CH)-CH_2-CH_3`
D. `Ph-CH_2-OH`

Answer

To solve the question regarding the reaction of `Ph-CH2-CH=CH2` with dilute `H2SO4`, we will follow these steps:

### Step 1: Identify the Reactant
The reactant is `Ph-CH2-CH=CH2`, which can be represented as:
- Ph = Phenyl group (C6H5)
- CH2 = Methylene group
- CH=CH2 = Alkene part

### Step 2: Understand the Reaction
The reaction involves the hydration of the alkene in the presence of dilute sulfuric acid (H2SO4). This is an acid-catalyzed hydration reaction where water is added across the double bond.

### Step 3: Protonation of the Alkene
In the presence of dilute H2SO4, the alkene double bond (C=C) will be protonated:
- The double bond between the second and third carbon (C2=C3) will react with H+ from H2SO4.
- The proton can add to either carbon of the double bond, but we will consider the more stable carbocation formation.

### Step 4: Formation of Carbocation
When H+ adds to the alkene, we can form two possible carbocations:
1. If H+ adds to C2, a secondary carbocation is formed at C3.
2. If H+ adds to C3, a primary carbocation is formed at C2.

The secondary carbocation is more stable due to hyperconjugation and inductive effects from the neighboring carbon atoms.

### Step 5: Nucleophilic Attack by Water
The water molecule (acting as a nucleophile) will attack the more stable carbocation:
- The nucleophile (H2O) will attack the carbocation at C3, resulting in the addition of an -OH group.

### Step 6: Final Product Formation
After the nucleophilic attack, we will have an alcohol. The structure will be:
- The phenyl group remains attached to C1.
- An -OH group is now attached to C3.
- The final product will be `Ph-CH(OH)-CH2-CH3`.

### Step 7: Deprotonation
The final step involves the deprotonation of the alcohol to form the stable product:
- The -OH group will lose a proton, resulting in the formation of the final product.

### Final Answer
The final product A is `Ph-CH(OH)-CH2-CH3`.

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