When 3-ethylpent-2-ene reacted with bromine water the major product as (IUPAC name):

Options

A. 3-ethyl pentan-3-ol
B. 3-ethyl pentan-3bromo-ol
C. 2-Bromo-3-ethylprentan-3-ol
D. 2-ethyl pentan-3-ol

Explanation

To determine the major product formed when 3-ethylpent-2-ene reacts with bromine water, we can follow these steps:

### Step 1: Understand the Structure of 3-Ethylpent-2-ene
- The name "3-ethylpent-2-ene" indicates a five-carbon chain (pent) with a double bond starting at the second carbon (2-ene) and an ethyl group (C2H5) attached to the third carbon.
- The structure can be drawn as follows:

```
CH3
|
CH3-CH-CH=CH-CH3
|
CH2-CH3
```

### Step 2: Identify the Reaction with Bromine Water
- When alkenes react with bromine water, they undergo an electrophilic addition reaction. In this case, bromine (Br2) adds across the double bond.
- The reaction can be represented as:

```
CH3-CH-CH=CH-CH3 + Br2 + H2O → Major Product
```

### Step 3: Apply Markovnikov's Rule
- According to Markovnikov's rule, when HX (where X is a halogen) adds to an alkene, the hydrogen atom will attach to the carbon with the greater number of hydrogen atoms already attached, while the halogen will attach to the carbon with fewer hydrogen atoms.
- In our case, the double bond is between C2 and C3. C2 has one hydrogen (CH) and C3 has two hydrogens (CH2). Therefore, the bromine (Br) will attach to C2 and the hydroxyl group (OH) from water will attach to C3.

### Step 4: Determine the Structure of the Major Product
- After the addition, we will have:

```
CH3-CH-CH(OH)-CH-CH3
|
Br
```

- The major product can be named based on the new substituents:
- The hydroxyl group (OH) is on C3.
- The bromine (Br) is on C2.

### Step 5: Write the IUPAC Name of the Product
- The IUPAC name of the product is derived from the longest carbon chain, which is still pentane, with the substituents noted:
- The bromine is on carbon 2 (2-bromo).
- The hydroxyl group is on carbon 3 (3-ol).
- The ethyl group remains on carbon 3.

Thus, the IUPAC name of the major product is **2-bromo-3-ethylpentan-3-ol**.

### Final Answer
The major product formed when 3-ethylpent-2-ene reacts with bromine water is **2-bromo-3-ethylpentan-3-ol**.

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