Question

Which reagent converts ethanol into bromoethane?

• A. KMnO$_4$
• B. PBr$_3$
• C. NaOH
• D. H$_2$SO$_4$

Hint:

Alcohols can be converted to alkyl halides using phosphorus halides ($\text{PX}_3$ or $\text{PX}_5$) or thionyl chloride ($\text{SOCl}_2$).
Specifically for bromination, $\text{PBr}_3$ is the standard choice.
For chlorination, $\text{PCl}_3$, $\text{PCl}_5$, or $\text{SOCl}_2$ are commonly used.

Answer 1

The Correct Option is B

Step 1: PBr3 reagent.
PBr$_3$ replaces -OH with -Br in primary alcohols: $3C_2H_5OH + PBr_3 \rightarrow 3C_2H_5Br + H_3PO_3$.
Answer: PBr3