The reagent used in the conversion of 1-butanol to 1-bromobutane is :

Options

A. `CHBr_(3)`
B. `Br_(2)`
C. `CH_(3) Br`
D. `PBr_(3)`

Answer

To convert 1-butanol to 1-bromobutane, we need to identify the appropriate reagent that facilitates this transformation. Here’s a step-by-step solution:

### Step 1: Identify the structure of 1-butanol
1-butanol is an alcohol with the molecular formula C4H10O. Its structure can be represented as:
\[ \text{CH}_3\text{CH}_2\text{CH}_2\text{CH}_2\text{OH} \]

### Step 2: Understand the reaction type
The conversion of an alcohol to a haloalkane (in this case, from 1-butanol to 1-bromobutane) is typically a substitution reaction. We need a reagent that can replace the hydroxyl (-OH) group with a bromine (Br) atom.

### Step 3: Choose the appropriate reagent
For the conversion of alcohols to alkyl bromides, phosphorus tribromide (PBr3) is commonly used. PBr3 reacts with the hydroxyl group of the alcohol, facilitating the substitution of the -OH group with a bromine atom.

### Step 4: Reaction mechanism
1. The oxygen atom in the -OH group of 1-butanol has lone pairs that can attack the phosphorus atom in PBr3.
2. This leads to the formation of an oxonium ion intermediate, where the -OH group is converted into a better leaving group.
3. A bromide ion (Br-) from PBr3 can then attack the carbon atom that was originally bonded to the -OH group, resulting in the formation of 1-bromobutane.

### Step 5: Write the final product
The final product of the reaction is:
\[ \text{CH}_3\text{CH}_2\text{CH}_2\text{CH}_2\text{Br} \]
This compound is known as 1-bromobutane.

### Conclusion
Thus, the reagent used in the conversion of 1-butanol to 1-bromobutane is **PBr3**.