The predominant product formed when `3-` methyl `-2-`pentene reacts with `HOCl` is

Options

A. `CH_(3)CH_(2)-underset(CH_(3))underset(|)overset(Cl)overset(|)(C)-CH(OH)CH_(3)`
B. `CH_(3)-underset(CH_(3))underset(|)overset(CH_(3))overset(|)(C)-underset(OH)underset(|)(C)H-CH_(3)`
C. `CH_(3)CH_(2)-underset(CH_(3))underset(|)overset(OH)overset(|)(C)-underset(Cl)underset(|)(C)H-CH_(3)`
D. `CH_(3)-underset(CH_(3))underset(|)overset(CH_(3))overset(|)(C)-underset(OH)underset(|)(C)H-CH_(3)`\

Answer

To determine the predominant product formed when 3-methyl-2-pentene reacts with HOCl, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structure of 3-Methyl-2-pentene**:
- The molecular structure of 3-methyl-2-pentene can be drawn as follows:
```
CH3-CH2-C(CH3)=CH-CH3
```
- Here, the double bond is between the second and third carbon atoms.

2. **Dissociation of HOCl**:
- HOCl dissociates into two parts: OH⁻ (hydroxide ion) and Cl⁺ (chloronium ion).
- This means that HOCl can act as an electrophile and a nucleophile in the reaction.

3. **Applying Markovnikov's Rule**:
- According to Markovnikov's rule, when HX (in this case, HOCl) adds to an alkene, the hydrogen (or the positive part, Cl⁺) will attach to the carbon with more hydrogen atoms, while the hydroxide (OH⁻) will attach to the carbon with fewer hydrogen atoms.
- In 3-methyl-2-pentene, the two carbons involved in the double bond are:
- C1 (CH2) has 2 hydrogens.
- C2 (C with CH3) has 1 hydrogen.
- Therefore, OH⁻ will attach to C2 (the carbon with fewer hydrogens), and Cl⁺ will attach to C1.

4. **Formation of the Product**:
- The product formed will be:
```
CH3-CH2-C(OH)(CH3)-CH2-Cl
```
- This can be represented as:
```
CH3-CH2-C(OH)-CH-CH3
```

5. **Final Product Structure**:
- The final structure of the product is:
```
CH3-CH2-C(Cl)(CH3)-CH2-OH
```
- This indicates that the hydroxyl group (OH) is attached to the second carbon, and the chlorine (Cl) is attached to the first carbon.

### Conclusion:
The predominant product formed when 3-methyl-2-pentene reacts with HOCl is:
```
CH3-CH2-C(OH)(CH3)-CH2-Cl
```